JUDY WOODRUFF: Good evening.

I'm Judy Woodruff.

On the "NewsHour" tonight: The U.S. House Judiciary Committee votes to hold Attorney General William Barr in contempt of Congress, a move the Democratic chairman says amounts to a constitutional crisis, as President Trump asserts executive privilege over the Mueller report.

Then: escalating tensions with Iran.

A year after the U.S. pulls out of the nuclear deal, Tehran signals it too will stop complying with parts of the landmark agreement.

Plus: inside a megafire.

Miles O'Brien on the race to protect California from devastating wildfires.

WILLIAM MAHONEY, National Center for Atmospheric Research: You really almost need to know every tree, every bush, every piece of grass and what its state is to really predict what's going to happen.

JUDY WOODRUFF: All that and more on tonight's "PBS NewsHour."

(BREAK) JUDY WOODRUFF: There is an escalating showdown between the two ends of Pennsylvania Avenue, and both sides are digging in their heels.

The chairman of the U.S. House Judiciary Committee says it has today taken a grave and momentous step.

Lisa Desjardins begins our coverage of the mounting clash over access to the entire Mueller report.

LISA DESJARDINS: Today, power moves in an escalating fight between branches.

REP. JERROLD NADLER (D-NY): The Judiciary Committee will please come to order.

LISA DESJARDINS: House Democrats called a rare hearing, the first step toward holding the attorney general in contempt of Congress.

Judiciary Chairman Jerry Nadler pointed to refusals to testify or to hand over an unredacted Mueller report.

REP. JERROLD NADLER: The Trump administration has taken obstruction of Congress to new heights.

LISA DESJARDINS: Simultaneously, the Trump administration made its own statement.

The Department of Justice sent Nadler a letter saying the contempt vote was unnecessary and that the president is exerting protective executive privilege over the documents Democrats want, meaning the agency will not turn them over.

That raised already heated temperatures at the Capitol.

REP. SHEILA JACKSON LEE (D-TX): I can only conclude the president seeks to take a wrecking ball to the Constitution of the United States of America.

For the first time in the history of the United States, a president is now exerting executive privilege over every aspect of life.

REP. CEDRIC RICHMOND (D-LA): Unfortunately, we have an administration that is choosing to have a temper tantrum that is designed to accomplish one thing.

And that one thing is to never let the real facts of the Mueller report come to light.

LISA DESJARDINS: Republicans charged that Democrats are playing politics.

REP. DOUG COLLINS (R-GA): What a cynical, mean-spirited, counterproductive and irresponsible step it is.

REP. MIKE JOHNSON (R-LA): Our Democrat colleagues have weaponized our critical oversight abilities.

LISA DESJARDINS: Republican Jim Sensenbrenner said the attorney general cannot hand over all of the Mueller report because grand jury testimony in particular must stay secret.

REP. JAMES SENSENBRENNER (R-WI): I think it is absolutely shocking that the majority of this committee is going to ask the chief law enforcement officer of the United States to commit a crime.

Shocking.

LISA DESJARDINS: Democrats rejected the argument as hyperbole.

REP. MARY GAY SCANLON (D-PA): Nobody is asking the attorney general to disobey the law.

We're asking the attorney general to obey the law and produce the Mueller report and the supporting documentation.

LISA DESJARDINS: At the White House, hard pushback at the committee and Chairman Nadler.

SARAH HUCKABEE SANDERS, White House Press Secretary: The attorney general is protecting information, grand jury information, confidential information that he cannot release.

The fact that the chairman knows that and continues to ignore it is absolutely absurd.

LISA DESJARDINS: Charging contempt of Congress is a power lawmakers have held since the 1700s, but it is rarely used against members of the executive branch, and even more rarely against the attorney general.

There was a sense of the stakes on both sides.

REP. DAVID CICILLINE (D-RI): I think people should recognize this is a deadly serious moment our democracy is being tested.

The rule of law and our basic institutions that have made our democracy the envy of the world are being tested.

REP. STEVE CHABOT (R-OH): Our Democratic colleagues seem to be on a mission.

They're determined to destroy Attorney General Barr, or at least discredit him in the eyes of the American people.

LISA DESJARDINS: The vote reflected the sentiments.

REP. JERROLD NADLER: Those in favor respond by saying aye.

Aye.

Opposed, no.

LISA DESJARDINS: A party-line split, with Democrats voting to charge the attorney general with contempt.

That resolution now moves to the full House.

JUDY WOODRUFF: This evening, it is being widely reported that Republican-led Intelligence Committee has subpoenaed Donald Trump Jr.

They intend to ask, reportedly, about his meeting with a Russian lawyer at Trump Tower in New York in 2016 and efforts by the Trump Organization to build a Trump high-rise in Moscow.

And Lisa joins me now, along with our White House correspondent, Yamiche Alcindor.

Hello to both of you.

So, from your perspective, Yamiche, what are these power moves about that the White House is making?

And what is their rationale for claiming executive privilege?

YAMICHE ALCINDOR: Well, this really comes down to historic power plays between the White House and Congress, each using their constitutional powers to really go head to head.

So, on the White House's side, the president is saying that Democrats are bitter about the 2016 election, and, as a result, they're carrying out partisan attacks.

Democrats, of course, say they're just going and doing oversight over the president, that he should be held accountable.

When it comes to exerting executive privilege, the White House has two rationales for this.

The first is that they say the material that Congress wants are actually illegal to release.

They say that there are issues with law enforcement sources, intelligence sources, and also grand jury material.

The other thing that White House aides have been telling me today, they -- the White House wanted to exert executive privilege before the hearing because they wanted to protect Attorney General Bill Barr.

They say that it's going to be harder for him to be held in contempt if the president is exerting executive privilege.

So this is really about the White House trying to have Bill Barr's back.

JUDY WOODRUFF: And, Lisa, you're talking to everybody on the Hill.

What are they saying?

What are Democrats saying this is all about?

And why do they reject the president's claim of executive privilege?

LISA DESJARDINS: That's so interesting about protecting the attorney general, because Democrats believe that the president already waived executive privilege here by allowing this testimony in the first place to Robert Mueller.

They said that's when he should have claimed executive privilege, not now.

So they say that that's not an argument that they can put stock in.

They also say that this is about more than what's happening.

Increasingly, Judy, I feel not just tension, but a larger concern from Democrats.

They see a potential erosion of checks and balances.

I talked to Representative Debbie Mucarsel-Powell from Florida.

She's an immigrant from Ecuador.

And she told me that she was thinking about South American dictators and how one small kind of erosion in checks and balances can hurt a democracy.

JUDY WOODRUFF: Huh.

And so back to you, Yamiche.

Where does this go from here?

And what is the White House saying about some of the Democrats calling this a constitutional crisis?

YAMICHE ALCINDOR: Well, the battle between White House and Congress is just getting started.

On the issue of contempt, the DOJ put out a very strong statement today saying that Attorney General Bill Barr shouldn't be bullied into releasing information that he thinks is illegal.

Then you're moving on to the idea of executive privilege.

There's this idea that there might be pushback between Robert Mueller and Don McGahn, the former White House counsel, to testifying before Congress.

The White House is saying that's separate issues and that they haven't made a determination whether or not they would allow that to go forward.

But I was talking to a White House source today.

That person said that the White House has already told Don McGahn not to turn over any documents to Congress because of issues of executive privilege.

Then, of course, this idea, broadening it out, Don Jr. being subpoenaed by the Republican-led Senate Intelligence Committee really goes to the heart of this idea that Congress might now start having fights between the president's own party and his son.

And then, lastly, this idea of constitutional crisis, I put the question directly to Sarah Sanders today and said, what do you make of the fact that there are people saying that the president's edging the country closer and closer to a constitutional crisis?

She said Democrats are the ones overstepping and that the president is on firm legal grounds here.

So she's backing up the president, as Democrats are, of course, sounding the alarm.

JUDY WOODRUFF: It's two totally different - - completely opposite sets of arguments.

LISA DESJARDINS: Right.

JUDY WOODRUFF: So, Lisa, we see the Congress moving closer to a full House vote on this question of contempt.

Historically, does that mean the House is likely to get what it wants?

LISA DESJARDINS: It's complicated, Judy.

What ends up happening in these cases, as I reported, executive branch contempt of Congress is very rare.

We have seen a couple of cases in recent years, one, White House counsel Harriet Miers under George W. Bush, and then Attorney General Eric Holder under President Obama.

In both of these those cases, Judy, it went to court.

The courts took a long time to decide and it went through appeal after appeal.

In the end, while the courts upheld the idea, the concept of Congress having this power, the court did not want to enforce it.

And the presidents at the time were basically able to run out the clock.

Those documents were obtained by Congress in both cases, but generally not until a new president was elected.

So running out the clock is very possible here for President Trump.

However, there's something exceedingly rare that some Democrats are talking about.

They have a different power of contempt that they're not invoking now.

It's called an inherent contempt of Congress, which means Congress itself can wedge -- can assess fines.

And, long ago, it used to actually imprison people itself.

Some Democrats are saying perhaps it's time for them to try and use that power, which has not been used since 1935.

JUDY WOODRUFF: I was going to say that has not been used for a very long time.

LISA DESJARDINS: No.

There used to be a House jail, of course, no longer.

JUDY WOODRUFF: All right.

Well, it's -- it seems to me it couldn't get much more serious than it is now, but we're watching.

LISA DESJARDINS: That's right.

JUDY WOODRUFF: You and Yamiche, thank you, both.

Yamiche Alcindor, Lisa Desjardins, we thank you.

In the day's other news: Iran's president declared that his country will step up enrichment of uranium if the 2015 nuclear deal is not renegotiated.

He warned of action in 60 days, unless European nations help mitigate U.S. sanctions.

The U.S. answered with new sanctions on Iran's metals industry.

And, in London, Secretary of State Mike Pompeo called for unity against Tehran.

MIKE POMPEO, U.S. Secretary of State: They have made a number of statements about actions they threaten to do in order to get the world to jump.

We will see what they actually do.

The United States will wait to observe that.

I am confident that, as we watch Iran's activity, that the United Kingdom and our European partners will move forward together to ensure Iran has no pathway for a nuclear weapons system.

JUDY WOODRUFF: The U.S. withdrew from the nuclear deal one year ago.

Today, Russia blamed Washington's actions for Iran's decision.

But Israel warned again that it will not let Iran obtain nuclear weapons.

We will delve into all of this right after the news summary.

This was Election Day in South Africa, and the ruling African National Congress faced strong challenges after 25 years in power.

Voters lined up with a chance to voice their frustration with corruption scandals and surging unemployment.

There were signs that overall turnout was low.

In this country, a Colorado teenager appeared in court a day after a school shooting that left one student dead and eight wounded; 18-year-old Devon Erickson kept his head down during the hearing.

He was arrested Tuesday along with a girl who is a juvenile.

There was no word on the motive for the shooting.

The U.S. Border Patrol reported today that more than 100,000 migrants were caught at the southern border in April.

That is for the second month in a row.

Meanwhile, a federal appeals court agreed Tuesday to making those seeking legal asylum wait in Mexico for immigration hearings.

The 9th Circuit Court in San Francisco let the policy stand pending a legal challenge.

Drivers from ride-share companies Uber and Lyft protested their pay in 10 major U.S. cities today.

They turned off their smartphone apps, cutting their connections to would-be customers.

Drivers argued that they are getting poverty wages, but the companies they work for are earning billions in profits.

AZIZ BAH, Rideshare Driver: All drivers, you know, everywhere in the country deserve a fair pay and fair treatment.

So we are hoping that this will make a big impact and make app-based companies listen to us.

JUDY WOODRUFF: The strike comes two days before Uber's initial public stock offering.

The company says it expects to be valued at $91 billion.

In Oregon, thousands of teachers staged a walkout today to lobby state lawmakers.

They demanded more funding for schools, and protested large class sizes and low graduation rates.

It's the latest in a wave of teacher strikes that began in West Virginia last year.

TV ads for prescription drugs will have to start showing list prices of the medications.

The U.S. Department of Health and Human Services announced the rule today.

It affects drugs that cost more than $35 for a month's supply.

Wal-Mart is raising its minimum age to buy tobacco products and e-cigarettes to 21 from 18.

The world's largest retailer says that the policy takes effect in July at all of its 5,300 U.S. stores.

The U.S. Food and Drug Administration had put Wal-Mart and others on notice for selling tobacco to minors.

On Wall Street, a late sell-off wiped out a rally as investors waited for trade talks with China to resume tomorrow.

The Dow Jones industrial average gained just two points to close at 25967.

The Nasdaq fell 20 points, and the S&P 500 slipped four.

And Britain's new royal baby now has a name.

He is Archie Harrison Mountbatten-Windsor.

The parents, who are Prince Harry, of course, and his American wife, Meghan Markle, announced it today, and they showed off their newborn baby for the first time.

The baby is seventh in line to the British throne.

Still to come on the "NewsHour": the president of Iran says his nation may soon restart banned nuclear activity; new tax information reveals the scope of President Trump's business losses; and much more.

Today, Iran announced it plans to stop complying with portions of the nuclear deal it signed with Western powers in 2015.

Iran stopped short of withdrawing from the deal altogether.

But, as Nick Schifrin reports, the announcement increases already escalating tensions with the United States.

NICK SCHIFRIN: The Iran deal made a fundamental trade: Iran restricted its nuclear program in exchange for sanctions relief.

One year ago today, the Trump administration withdrew from the deal, and has since reimposed sanctions.

For the last year, Iran complied with the deal, but, today, Iran said it would not abide by all the deal's restrictions.

Number one, the deal limits Iran's stockpiles of low-enriched uranium, which is nuclear fuel, and heavy water, which is used to operate a nuclear reactor.

Today, Iran said it would no longer adhere to those limits.

And if Iran does exceed the caps, it will no longer be in compliance with the deal.

And then Iran threatened even more dramatic actions.

To produce a bomb, you typically need to enrich uranium at 90 percent.

Before the deal, Iran enriched uranium at nearly 20 percent, which the U.S. said meant Iran could break out and create a bomb within a few months.

After the deal, Iran enriched uranium at 3.67 percent and removed most of its centrifuges, moving breakout time to more than a year.

Today, Iran said if it doesn't receive economic benefits allowed by the deal in the next 60 days, it not would adhere to -- quote -- "any uranium enrichment limit."

And it would also take a plan to convert the Arak nuclear reactor so it doesn't produce large amounts of plutonium and cancel it.

Despite those threats, Iranian President Hassan Rouhani said today Iran was still in the deal.

HASSAN ROUHANI, Iranian President (through translator): Our nation should know that we have not withdrawn from the nuclear deal.

They shouldn't think that the nuclear deal doesn't exist anymore.

Today, we announced a reduction, not withdrawal.

NICK SCHIFRIN: And for more on this, we turn to Iran's ambassador to the United Nations, Majid Takht-Ravanchi.

Ambassador, thank you so much for joining the "NewsHour" today.

You have gone a whole year since the Trump administration pulled out of the Iran deal without responding in a major way.

Why respond today?

MAJID TAKHT-RAVANCHI, Iranian Ambassador to the United Nations: Over the last year, we exercised extreme patience in order to show that Iran is ready, Iran is ready to take extra mile, in order to show that it is sincere in its implementation of the nuclear deal.

But, unfortunately, due to U.S. bullying of even its closest allies, we have not received the economic benefit that we were promised to receive based on the nuclear deal.

And then we were left with no other option than to say that, for 60 days, we are going to stop implementing or to cease performance of some of our obligations, voluntary obligations, based on the nuclear deal.

And we will see what will happen during the next 60 days.

The window of diplomacy is not closed.

We believe that Iran will speak, will negotiate with the partners, the remaining participants of the JCPOA, and we will see what will be the outcome of the negotiations.

NICK SCHIFRIN: Ambassador, you say that you were left with no other option, but why do you need to enrich uranium at a higher level than 3.67 percent?

What's your intentions by doing that -- or possibly doing that?

MAJID TAKHT-RAVANCHI: Well, no, for the time being, we are adhering to the JCPOA on the limit of the enrichment, the level of enrichment.

What we have said is, for the next 60 days, we are going just to be free for our stockpile.

We are not talking about enriching more than 3.67 percent for the next 60 days.

(CROSSTALK) NICK SCHIFRIN: Right, but President Rouhani did say today that you would enrich higher than 3.67 if you don't get those economic incentives, which haven't come so far.

MAJID TAKHT-RAVANCHI: Of course.

Of course we will.

Of course we will.

The reason is that our partners have had more than enough time, for the last year-and-a-half or so, to -- for the last year or so -- I'm sorry -- to compensate what the Americans have done to the JCPOA.

So if they cannot do it in the next two months, that means that the political will is not there.

And then we will act in accordance with our national interests.

NICK SCHIFRIN: Today, President Trump said that he still hoped to meet with Iran's leadership.

Does Iran have any interest in meeting with President Trump?

MAJID TAKHT-RAVANCHI: There is -- I mean, there is no utility in meeting somebody who carelessly tear apart, you know, an international agreement.

It wasn't an agreement between Iran and the United States.

Other countries, the European Union were part of it.

So, all of a sudden, we see that the president comes and says, I don't like it because of so many reasons, because the former president took the initiative to sign such an agreement with Iran.

So, how can we trust somebody who carelessly and recklessly do something like this?

NICK SCHIFRIN: Ambassador, quickly, in the time we have left, there are some people who I'm talking to here who are experts on Iran fear that the speech by President Rouhani today will allow hard-liners here in the U.S. and perhaps Israel a stronger case to argue that Iran is not trustworthy.

What's your response to that?

MAJID TAKHT-RAVANCHI: I think the hard-liners, as our foreign minister has coined it, four B's, Bibi Netanyahu, Bolton, bin Zayed, and bin Salman, they are doing whatever they can, no matter what Iran does.

So it doesn't matter how we are dealing with JCPOA.

Their agenda is to provoke.

Their agenda is to agitate the situation.

Their agenda is to prepare a war against Iran.

We are not trying to wage war against anybody, but, definitely, we will defend ourselves no matter what.

NICK SCHIFRIN: Ambassador Majid Ravanchi, ambassador of Iran to the United Nations, thank you so much for your time.

MAJID TAKHT-RAVANCHI: Thank you, sir.

NICK SCHIFRIN: And now with me for the Trump administration's view is Brian Hook, the State Department's representative for Iran.

Brian Hook, thank you for coming back to the "NewsHour."

You just heard Ambassador Ravanchi accuse the U.S. of saying that your real intention is to provoke Iran and to -- quote -- "prepare for war."

Is that the U.S. intention?

BRIAN HOOK, State Department Special Representative for Iran: I didn't really hear what he said.

I can just say today what we saw with the Iranian regime is another example of nuclear blackmail.

This is a strategy that they have used very effectively for many years.

They do it to intimidate other nations, so that they then give Iran the economic benefits that it think it -- that they think they deserve.

And, in fact, Iran doesn't need to be enriching any fissile material at a level that is above what is required for a peaceful nuclear program.

And so we're very happy to be outside of the Iran nuclear deal.

We have a lot more freedom to deter Iran and prevent it from ever acquiring a nuclear weapon.

NICK SCHIFRIN: So, you call it nuclear blackmail.

Let me go into what President Rouhani said today.

He said that Iran would no longer abide by the caps on heavy water and low-enriched uranium.

He threatened in 60 days to do more when it came to enrichment.

But they are in the deal.

And, as you heard the ambassador say, diplomacy is still an option.

So, in some ways, is their response restrained?

BRIAN HOOK: No.

I think -- as I said earlier, I think this is the Iranian regime, the world's leading sponsor of terrorism, threatening to enrich levels of uranium beyond what is necessary for a peaceful nuclear program.

They have also used the nuclear program to - - as cover to expand their range of activities, to run an expansionist revolutionary foreign policy around the Middle East.

And it runs all the way from Lebanon to the Houthis in Yemen.

And so what we have done outside of the deal is to drive up the costs of Iran's very expansionist foreign policy.

And also being outside of the deal, with the enormous economic pressure that we're able to put on this regime, we're in a much better position to achieve our national security goals outside of the deal.

NICK SCHIFRIN: I think your critics would point out that it would be easier to confront Iranian malign behavior while restricting their nuclear program.

BRIAN HOOK: Well, Iran is still in the Iran nuclear deal.

We're outside of it.

And so we're not under any of those restrictions any longer.

When we were in the deal, we weren't able to use any of our oil and banking sanctions against Iran to change their malign behavior around the Middle East.

We have now sanctioned almost 1,000 Iranian individuals and organizations for a range of activities around the nuclear program, the missile program, the regional aggression, and the arbitrary detention of American citizens.

We are seeing a difference.

Iran has had to cut its defense budget for two successive years.

Its biggest client in the Middle East, Hezbollah, has been making a public appeal for donations because the money from Iran is running out.

So we're very happy with the positive impact that we're having just in the one year -- and today is the one-year anniversary of us getting outs of the Iran deal.

NICK SCHIFRIN: Brian Hook, we have about a minute left, so I want to ask you about that maximum pressure campaign.

You just talked about almost 1,000 people or entities.

Today, you announced new sanctions on Iranian steel, aluminum and copper.

One of the goals that you and I have talked about is getting Iran back to the table to renegotiate what you have called a bigger nuclear deal.

Is there any evidence that your maximum-pressure campaign is convincing Iran to come back to the table?

BRIAN HOOK: Well, we have a goal of getting to a new and better deal to succeed the existing Iran nuclear deal, which is only limited to the nuclear program.

We are interested in an agreement that would address the nuclear program, the missile program, regional aggression, human rights abuses, and the like.

Secretary Pompeo made that very clear about a year ago, the kind of demands that we that are -- we have placed on the Islamic Republic to behave more like a normal nation and less like a revolutionary cause.

Putting in place that sort of clarity, we think, has been very helpful for the international community and it's highlighted Iran's regional aggression.

And we're having more countries come our way over the last year because of our diplomacy.

NICK SCHIFRIN: Brian Hook, special representative for Iran at the U.S. State Department, will have to leave it there.

Thank you so much.

BRIAN HOOK: Thanks, Nick.

NICK SCHIFRIN: We now turn to Ambassador Wendy Sherman.

She was the lead U.S. negotiator for the nuclear agreement with Iran during the Obama administration.

And she's now a senior fellow at the Belfer Center at Harvard.

You heard me ask Brian Hook whether the U.S. intention is to provoke Iran, is to wage war, which is what we heard from the Iranian ambassador.

Do you believe the U.S. intention is to provoke Iran?

WENDY SHERMAN, Former U.S.

Undersecretary of State for Political Affairs: Well, I hope that the U.S. intention is not to provoke Iran, to leave the deal, or to provoke Iran into a regional conflict.

Indeed, I think that President Rouhani very carefully threaded the needle today, not leaving the deal, but take -- beginning to take steps to say, please, let's not escalate the situation.

I wish the Trump administration were as measured in its approach.

And I would say to Brian Hook that -- and to the Trump administration -- what have they gotten as a result of withdrawing from this deal a year ago?

There is more malign behavior in the Middle East, not less.

Americans are still in prison and missing in Iran.

The Iranian people do not have more freedom.

And the administration has set Iran back on a path to perhaps working to obtain nuclear weapons, exactly what we stopped from happening.

NICK SCHIFRIN: So you just said the U.S. has led Iran onto that path.

But, as I asked the ambassador, why should Iran enrich more than 3.67?

What's wrong with where they are right now?

And why isn't that criticism valid?

WENDY SHERMAN: Iran is very happy to stay at 3.67 percent in its enrichment of uranium, if, indeed, the joint comprehensive plan of action, the Iran deal, stays in place.

And those limitations are for quite some time, and it is all about... (CROSSTALK) NICK SCHIFRIN: Although, as you know, your critics say not long enough.

WENDY SHERMAN: Yes, I know they say it's not forever.

It's at least solid for 15 years that you cannot go above a certain stockpile limit.

You can't go above 3.67 percent.

But even after that, there are limitations on what Iran can do, and there is the most extensive monitoring and inspection of Iran of any country in the world.

NICK SCHIFRIN: Iran said, as you heard the ambassador, that we will enrich beyond 3.67 if we don't get the incentives that the JCPOA, that the Iran deal, intended for Iran to get.

The Europeans would be the ones to help deliver that.

Can they deliver the incentives economically to keep Iran within this deal?

WENDY SHERMAN: I think it's very tough, because, as I think you know quite well, the U.S. secondary economic sanctions, which say that, if you deal with the Central Bank of Iran, you can't deal with an American bank, are incredibly powerful, because, quite frankly, virtually every company in the world would choose an American bank over the Central Bank of Iran.

And when you marry that with the oil sanctions that -- with the administration trying to go to zero exports allowed around the world, they're very powerful sanctions.

The U.S. has to be careful in what it does, though.

If we use these sanctions too much, people will begin to say that we should no longer have the dollar as the reserve currency for the world.

The other thing I would point out, Nick, is, in my view, there are tactics here, but no strategy, and certainly no consistent strategy.

If we take a look at North Korea, if we take a look at Venezuela, if we take a look at how we're dealing with the Chinese and the Uyghurs, we see a very different set of standards.

NICK SCHIFRIN: The U.S. earlier this week deployed a carrier group to the Middle East, as well as a bomber squadron, in response to intelligence, according to the officials I spoke to, in which Iran was planning to target U.S. troops and also target U.S. allies, Saudi Arabia, the United Arab Emirates.

Doesn't that show the Iran deal didn't improve Iranian behavior?

WENDY SHERMAN: We never said that it would improve Iranian behavior in the region.

What we did say is that we needed to get the nuclear weapon off the table, so it wouldn't deter our actions and our partners and our allies' actions in the region.

And we could then use all of the sanctions we still had on Iran to press them to the table to deal with their malign behavior, the state sponsorship of terrorism, their human rights abuses, and their keeping Americans in prison, and not bringing back missing Americans to our home.

NICK SCHIFRIN: Very quickly.

I only have a little -- a few seconds left.

WENDY SHERMAN: Sure.

NICK SCHIFRIN: Iran's strategy seems to be waiting out the Trump administration.

If a Democrat is elected in 2020, should he or she rejoin the deal and/or try and expand it?

WENDY SHERMAN: I think every Democratic candidate that I have heard have said that they would immediately rejoin the deal.

But, like in any arms control negotiation, you usually have a follow-on agreement.

NICK SCHIFRIN: Wendy Sherman, lead U.S. negotiator for the Iran deal, thank you so much.

WENDY SHERMAN: Thank you.

NICK SCHIFRIN: And for a view from the streets of Iran, we have more online, where I talk to special correspondent Reza Sayah in Tehran.

That's at PBS.org/NewsHour.

JUDY WOODRUFF: Congressional Democrats are expected to decide tomorrow whether they will go to court to obtain President Trump's recent tax returns.

The president broke with modern tradition by refusing to release his returns.

Democrats and other experts have questioned whether there could be information about foreign investors, about debts or other business arrangements in those returns.

Today, the New York State Senate approved a bill that would allow the president's state tax records to be turned over to Congress.

As William Brangham tells us, this line of inquiry picked up new fuel overnight after a New York Times investigation shed light on the president's past tax records and his large business losses.

WILLIAM BRANGHAM: Judy, The Times' investigation found that at the very moment Donald Trump was portraying himself as the most successful dealmaker of the 1980s and '90s, his actual balance sheet told a very different story.

The Times' analysis found Mr. Trump lost more than $1 billion between 1985 and 1994.

The report says -- quote -- "Year after year, Mr. Trump appears to have lost more money than nearly any other individual American taxpayer."

Those combined losses, the article contends, enabled him to avoid paying income taxes for eight years.

The president and his legal team have called The Times' report inaccurate.

I'm joined now by one of the reporters who broke this story, Russ Buettner of The New York Times.

Russ, thank you very much for being here.

You have painted this really remarkable portrait of this decade in Donald Trump's financial life.

Help us understand, why was he losing so much money during this time?

RUSS BUETTNER, The New York Times: Well, if you look back at the records from that era, he was buying things at extraordinarily high prices, and then taking on even more debt to build them out to his design.

And then the revenues that he brought in never supported that debt load.

So, with each acquisition, he would go further into the red ink, and the losses just mounted as the years progressed.

WILLIAM BRANGHAM: And what were these ventures, for people who are not that familiar with his history?

RUSS BUETTNER: He originally started building apartment buildings.

He would make a condominium building.

That would sell through and he would keep the retail space.

Then he branched out into a variety, a very eclectic collection of things.

He bought an offshoot of the NFL.

He bought a football team.

He bought an airline.

He started opening casinos that were extraordinarily expensive.

He bought a landmark New York City hotel.

And all of that just mounted up to about $3 billion in debt he took on over just about a five-year period.

WILLIAM BRANGHAM: And, as your report points out, he did have some successful ventures, but, in any given year, it seems, the losses from other ventures swamped those returns.

RUSS BUETTNER: That's exactly right.

He would -- he's constantly sort of changing focuses.

There was a period of time that lasted about two years where he would buy, with borrowed money, large holdings in a public corporation, leak news that he had bought that, and that he might take the company over, and as soon as the stock went up, he would sell.

He made about $60 million over a couple of years doing that.

And then the market figured out that he wasn't going to take over the companies, and it stopped reacting.

That sort of ended.

But it was -- like that, there were these ventures that he did make money on.

But the losses from his company, his companies, his other enterprises, would wash away all his tax liability for even those extraordinary gains.

WILLIAM BRANGHAM: The president, as you know, has said, first off, that everybody was doing this back in the '80s and '90s.

And then he also said that your reporting was inaccurate.

Given that you don't actually have a signed copy of President Trump's tax returns, how did you compile this data?

And how do you know it is actually accurate?

RUSS BUETTNER: What we have is a printout from President Trump's tax transcript, which is a printout from an official database the IRS has kept since the 1960s of every tax return that's filed by every individual every year.

There are internal quality controls on that data.

It's used for a variety of policy-setting reasons.

They use it to target audits.

And they bring printouts from it to audits.

And if you wanted to request yours, you could file that request with the IRS, and they would give it to you as an official record of the return you filed.

It's, in fact, a very reliable record.

It's been used for very important things for a long time.

WILLIAM BRANGHAM: Lastly, this is, of course, coming amidst the fight of congressional Democrats trying to get more recent tax returns from the president.

What might those returns tell us that we don't now know?

RUSS BUETTNER: We're guessing into a vacuum a little bit, because we just really don't know.

But we could certainly tell for the first time maybe if his claims of wealth are really accurate.

We would be able to see how profitable his businesses are.

He's reported on his disclosure forms revenue figures, not profitability.

And profitability has been a problem for Donald Trump throughout his career.

We could tell what the sources of those incomes are.

We could tell whether he has any properties that are in jeopardy.

We could tell if he's got partners that he hasn't disclosed.

We could tell if he's got more debt than what he's allowed and who he's borrowed money from.

And we could look for conflicts of interest that might not be apparent now between his public policy and all the countries around the world where he has investments in money-earning properties.

WILLIAM BRANGHAM: All right, Russ Buettner of The New York Times, thank you very much.

RUSS BUETTNER: Thanks for having me.

JUDY WOODRUFF: As the first person to declare his candidacy for the Democratic Party's 2020 presidential nomination, John Delaney has been running for president for almost two years.

The businessman and former Maryland congressman now faces a crowded field and the challenge of taking on some well-known names.

And John Delaney joins me now.

Welcome again to the "NewsHour."

REP. JOHN DELANEY (D-MD), Presidential Candidate: Thank you for having me, Judy.

JUDY WOODRUFF: So, John Delaney, quickly on our lead story tonight, we're reporting on President Trump exerting executive privilege.

He will not turn over to Congress the full Mueller report.

Do you think, again, just quickly, this moves the Congress any closer to impeachment proceedings?

REP. JOHN DELANEY: Well, I think it moves the Congress closer to having more investigations and trying to subpoena the report and those things, as I think they should as part of their oversight responsibility.

I wouldn't say it necessarily moves them closer or not to impeachment.

I think what the Congress and what Speaker Pelosi are going to focus on is making sure the Congress fulfills its investigative and oversight responsibilities.

And I think they're going to push to get that report, as they should.

JUDY WOODRUFF: All right, let's talk about you and your campaign.

REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: As we said, it's a crowded field, more than 20 people running for president, serious candidates.

How does John Delaney stand out from all the others?

REP. JOHN DELANEY: Well, I'm a problem-solver by nature.

And I think that's what we really need.

Our next president needs to be a responsible president.

And a responsible president would bring this country together, right, remind us that this notion of common purpose is central to who we are, and actually start find some common ground and solving problems and bring some new big ideas.

And that, in many ways, makes me a more centrist and moderate candidate.

I'm probably the most moderate candidate in this field, because... JUDY WOODRUFF: Really?

REP. JOHN DELANEY: Yes, I think so, because I'm very focused on problem-solving, right?

I really want to get things done, because that's what I think this country needs.

I think Congress and the legislative process and the president have largely been absent in getting things done that matter to the American people.

And I want to bring back this notion that we can actually tackle these problems, and we can kind of achieve the potential that we have as a people.

But we have to work together to do it.

JUDY WOODRUFF: Well, speaking of moderation, you have said about some of your more liberal opponents or, I should say, competitors, you have talked about Medicare for all, which some of them advocate, as a -- quote -- "half-baked socialist policy."

You would support, instead, a public option... REP. JOHN DELANEY: Absolutely.

JUDY WOODRUFF: ... Medicare-like option for people under the age of 65.

That wouldn't cover every American, though, would it?

REP. JOHN DELANEY: Well, I'm actually -- I do have a universal health care plan that actually does cover every American.

A public option is something I would do right away.

That's kind of a first-100-day agenda that I think I can get done to improve health care for the American people right away.

But then I would push for my plan to create universal health care, where every American has health care as a right.

I just don't believe the way to accomplish universal health care is with a government-only program.

That's why I think the Medicare for all proposal is in fact bad policy, because it makes the government the only provider of health care.

And we have ample evidence to suggest that, if the government is the only payer in health care, it will never pay enough.

Right now, Medicaid and Medicare don't cover costs.

So, if you take private insurance out of the equation, I think the quality of health care will go down.

JUDY WOODRUFF: So you would keep private insurance... REP. JOHN DELANEY: Absolutely.

JUDY WOODRUFF: ... but still find a way to cover everybody?

REP. JOHN DELANEY: And you can do that.

Right?

My proposal leaves Medicare alone.

It creates a new government plan that everyone gets from when they are born until they're 65.

We roll Medicaid into that.

So, that means everyone has health care from when they're born to the end of their life.

But I also allow them to opt out, get a small tax credit, buy their own plan, or to do what Medicare beneficiaries do, which is to buy supplemental plans.

That creates a mixed model of a government plan, plus private health insurance.

It's a much healthier and stronger health care market.

And it gives the American people what they fundamentally want, which is choices and options.

JUDY WOODRUFF: All right, let's talk very quickly.

REP. JOHN DELANEY: Sure.

JUDY WOODRUFF: You have spent a lot of time campaigning all over the country, early primary states.

REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: Your home state of Maryland... REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: ... big city, Baltimore... REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: ... has a lot of problems, city problems, violence, tensions between the races, poverty.

What would you do in the short run to help cities like Baltimore?

REP. JOHN DELANEY: I think we have to invest in them, at the end of the day.

I think nothing happens unless someone invests.

And I think, for many of these communities, there's been chronic underinvestment, in public education, in job creation, in transportation.

JUDY WOODRUFF: And where would the money come from?

REP. JOHN DELANEY: Well, you have got to make it a priority, because I think, if you don't make it a priority, you actually spend more money.

I think the cost of doing nothing is not nothing.

And we are seeing firsthand, with the state of Maryland's failure to really invest in Baltimore the way they should have, that all citizens of Maryland are actually now paying a much higher price.

JUDY WOODRUFF: I want to -- there are so many things I want to ask you.

Your campaign, you resorted to some pretty unconventional means to try to spread out the number of people donating to your campaign.

You at one point, I think two months ago, said you were going to give $2 of your own money for every charitable contribution to charities... REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: ... for anybody who contributed to your campaign.

So how many more people did you pick up?

REP. JOHN DELANEY: We got quite a bit.

You know, we got thousands and thousands of additional donors for it.

It was really simple, Judy, because we have to get 65,000 donors to be on the debate stage.

JUDY WOODRUFF: In order to participate in the debates.

REP. JOHN DELANEY: You don't really have to.

I have qualified for the debates because of my performance in the polls.

But this is another way to also... JUDY WOODRUFF: But you still need to raise money from 65,000?

REP. JOHN DELANEY: Well, it's an either/or.

You either qualify through the polls or you qualify with 65,000.

But we want to get both.

And I would rather actually give money to charity than to give money to digital marketing firms, because that's kind of what you have to do to get that many donors.

JUDY WOODRUFF: Are you at 65,000?

REP. JOHN DELANEY: We're not there yet, but we're making good progress.

JUDY WOODRUFF: We said you were the first Democratic candidate to announce.

You announced back in July 2017.

REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: I think nobody has been campaigning more than you have in the state of Iowa.

There have been hundreds of campaign events, Iowa, New Hampshire, and other states.

But you are still at 1 percent in the polls.

REP. JOHN DELANEY: Well, we actually.. JUDY WOODRUFF: Well, and let me just say... REP. JOHN DELANEY: Yes.

JUDY WOODRUFF: ... that others who have gotten in the race, they're ahead of you.

Why do you think you have struggled to get your identity out there?

REP. JOHN DELANEY: Well, we're doing better in other polls.

We just had a poll in New Hampshire that had us doing better.

We had a poll in Iowa a couple weeks ago that had us at a higher rate.

I think we're doing great on the ground.

I think this race is wide open.

Right?

We have eight offices open in Iowa.

We have got as big of a campaign team as anyone else.

Four county chairs of the 99 counties in Iowa have already endorsed me.

None of the other candidates combined have any endorsements from any county chairs, right?

I have been to all 99 counties in Iowa.

I have campaigned everywhere.

I think this race is wide open.

They're not going to caucus in Iowa for 10 months.

And I just think we're in a really good position on the ground there.

And I think, at the end of the day, my ideas are better.

And the debates will, I think, start making that point.

JUDY WOODRUFF: On May the 8th, 2019, John Delaney, thank you very much.

REP. JOHN DELANEY: It's so nice to be here.

Thank you.

JUDY WOODRUFF: It's been six months since the most deadly and destructive fire in California history, the Camp Fire.

Tonight's edition of PBS' "NOVA" is a harrowing first-person account of that disaster and where it fits into a global trend toward more frequent massive infernos.

The documentary, "Inside the Megafire," comes from Miles O'Brien.

And, for us, he explores how researchers are breaking new ground in understanding the dangerous spread and intensity of the flames.

It's part of our regular series on the Leading Edge of science.

MAN: This has got potential for a major incident.

MILES O'BRIEN: When first-responders arrived at the Camp Fire, the flames were already so fierce and the winds so strong, they had trouble getting close to the fire.

MAN: Eyes on the vegetation fire.

Got about a 35 -mile-per-hour sustained wind on it.

MILES O'BRIEN: Fanned by high winds, fed by drought-stressed trees, the fire moved incredibly fast, consuming an acre of forest every second.

A horrific scenario was unfolding that also presented an opportunity for scientists to better understand how wildfires spread.

CRAIG CLEMENTS, Meteorologist, San Jose State University: We're not going to -- we're not going to get through here.

They are doing active suppression right there.

Let's go up and see what we can find.

MILES O'BRIEN: So meteorologist Craig Clements and his team from San Jose State University sped right toward the inferno.

In the crosshairs, Paradise, California, a town of 26,000 nestled in the Sierra Mountains.

It was the morning of November 8, 2018, and everyone who lived there had to leave in a hurry.

MAN: Just got to get the (EXPLETIVE DELETED) out of Dodge.

This is getting heavy.

MILES O'BRIEN: They were forced to run a gauntlet through flames.

There are only four roads that lead off the mountain.

And all of them were perilous.

WOMAN: Oh my God, there's fires everywhere.

I don't want to die here.

I don't want to die.

MAN: Please get out of town.

And as you're going out of town, please be careful.

MILES O'BRIEN: With the frantic exodus still under way, we drove in the opposite direction, eventually meeting up with Clements and his team close to the fire line.

They had found a relatively safe vantage point to gather some unprecedented data.

We are driving in a one-of-a-kind custom rig.

The scientists hope to use it to peer into the fire in a way that no one else has before.

CRAIG CLEMENTS: We need to better understand fire spread.

And the meteorological data is one of the key components.

And yet we never measure things on an active wildfire.

We usually use a satellite.

We see plumes in the radar, which is great.

But we're not really seeing what's going on right here.

MILES O'BRIEN: Plumes, the columns of smoke and gas that rise from the flames, are more than a sign of fire.

They also create their own weather.

And Craig Clements suspects that they actively spread the fire.

But how?

To understand, he aims a sophisticated lidar right at the plume.

Lidar is like radar that uses a laser beam instead of radio waves.

It bounces off the smoke particulates as they are propelled by the wind and returns information about speed and direction.

CRAIG CLEMENTS: We have been able to slice through a plume with our lidar.

And we have been able to measure the rotation and the wind field associated with the rotating column, and so that's pretty exciting.

MILES O'BRIEN: The plumes at fires like these are complicated systems.

As hot air rises, cooler air rushes in.

It's called fire-induced wind.

CRAIG CLEMENTS: We don't know how that fire-induced wind from the plume interacts with pushing the fire front.

If the plume goes up, does any air or smoke come back down?

And if it does come back down, can that spread the fire in different directions?

It's these interactions that we call fire atmosphere interactions, and we don't have a great handle on how they propagate fire spread.

MILES O'BRIEN: A big factor in the exponential spread of the Camp megafire, spotting.

Hot embers, also called firebrands, launched and carried by 50-mile-an-hour winds landed as much as a mile ahead of the fire front.

New spot fires started again and again, rapidly, randomly.

But exactly how spotting fuels the growth of megafires is one of the big unknowns in wildfire science.

CRAIG CLEMENTS: So, it's still blowing northeasterly.

MILES O'BRIEN: Craig Clements hopes his work might lead to some answers.

CRAIG CLEMENTS: This is a real strong low-level jet coming down off the mountains.

MILES O'BRIEN: Right now, wildfire prediction models are not sophisticated enough to factor in all of the complexities of the atmosphere and terrain.

And they don't account for spotting at all.

CRAIG CLEMENTS: We are trying to forecast how many spot fires there will be, and that's something no model right now can handle.

MILES O'BRIEN: At the National Center for Atmospheric Research in Boulder, Colorado, they're leveraging their expertise modeling weather and climate to give teams on the ground battling a wildfire a better sense of what the future holds.

WILLIAM MAHONEY, National Center for Atmospheric Research: Fire is very challenging to predict because there are a lot of factors that are involved that are not really atmospheric or traditionally atmospheric.

MILES O'BRIEN: Atmospheric scientist William Mahoney showed how the latest models can see trouble as it brews, in this case, close to home.

The Cold Springs Fire happened 16 miles west of Boulder in the little town of Nederland in July of 2016.

WILLIAM MAHONEY: There was good data from this particular event in terms of how the fire progressed, the burned area boundary.

And that made for really good verification data for our model, so we can then use that to fine-tune the rate of spread and the heat content and flame length information.

MILES O'BRIEN: The model is designed to allow them to predict the rate of spread of the fire 18 hours in advance, and run what-if scenarios for different moisture levels in the forest.

WILLIAM MAHONEY: We're trying to simulate the general characteristics of a fire, but we will definitely not be able to say at this second and then in this location a tree is going to burn or a building is going to burn.

You really almost need to know every tree, every bush, every piece of grass and what its state is to really predict what's going to happen.

MILES O'BRIEN: Fire ecologist Jennifer Balch and her team from the University of Colorado are trying to find more precise, more efficient ways to assess forest health, so that the models can be more accurate.

She is focused on eight 30-by-30-meter plots, many of which were heavily damaged by the Cold Springs Fire.

Their work begins on the ground in the traditional way.

WOMAN: It looks like 3.8.

MILES O'BRIEN: Once the trees are precisely measured and characterized on terra firma, Balch and her team fly a drone 100 feet above each plot.

The drone carries sensors that capture the same parts of the spectrum as those on board NASA satellites.

By comparing these higher-resolution drone scans with images from space, she hopes to find the dots and connect them.

The Holy Grail?

Understanding how a forest is doing from space.

JENNIFER BALCH, University of Colorado Boulder: My hope is that we can actually get away from the intensive fieldwork and use drone-based observations, airborne, and satellite-based observations to understand what's going on across thousands of trees.

MILES O'BRIEN: To better understand the big picture, scientists who study wildfires need to explore them up close.

On a good day, it's laborious, on a bad day, perilous.

MAN: If anything happens, we got to go, and we -- our escape route is this way.

MILES O'BRIEN: By the time it was over, the Camp Fire was the deadliest and most destructive in California history; 85 people died.

Nearly 19,000 structures were destroyed.

For scientists, the stakes justify the risk.

For the "PBS NewsHour," I'm Miles O'Brien in Paradise, California.

JUDY WOODRUFF: Well, that's something.

There is much more in tonight's program than we could include here.

"NOVA"'s "Inside the Megafire" airs on most PBS stations and streams online tonight at PBS.org/NOVA.

And that's the "NewsHour" for tonight.

I'm Judy Woodruff.

Join us online and again here tomorrow evening.

For all of us at the "PBS NewsHour," thank you, and we'll see you soon.