ROBERT COSTA: Battles abroad, battles at home.

President Trump changes course in Afghanistan, goes to war with Republicans, and threatens a shutdown over a border wall.

I'm Robert Costa.

We cover it all, tonight on Washington Week.

PRESIDENT DONALD TRUMP: (From video.)

We are not nation-building again.

We are killing terrorists.

ROBERT COSTA: President Trump expands the U.S. role in Afghanistan, convinced by his generals that the 16-year conflict has reached a critical juncture.

SECRETARY OF DEFENSE JAMES MATTIS: (From video.)

We're not winning in Afghanistan right now.

ROBERT COSTA: The president also puts Pakistan on notice.

PRESIDENT DONALD TRUMP: (From video.)

We can no longer be silent about Pakistan's safe havens for terrorist organizations.

ROBERT COSTA: What will victory look like under the Trump plan?

On the campaign trail, the president fires up his base.

PRESIDENT DONALD TRUMP: (From video.)

They're trying to take away our culture.

They're trying to take away our history.

And our weak leaders, they do it overnight.

ROBERT COSTA: And throws down an ultimatum to Congress: fund a border wall, or else.

PRESIDENT DONALD TRUMP: (From video.)

If we have to close down our government, we're building that wall.

ROBERT COSTA: So, what happened to the plan to have Mexico pay for it?

We'll get answers and analysis from Julie Pace of The Associated Press, Jake Sherman of POLITICO, Nancy Youssef of The Wall Street Journal, and Dan Balz of The Washington Post.

ANNOUNCER: Celebrating 50 years, this is Washington Week.

Once again, live from Washington, moderator Robert Costa.

ROBERT COSTA: Good evening.

As Hurricane Harvey barrels towards the Texas Gulf Coast, we send our thoughts to those who call the region home.

Please, stay safe.

And here in Washington, a different type of storm is brewing between the president and congressional Republicans over the debt ceiling, a budget to keep the government running, and funding for a border wall.

And the president continues to pick fights with fellow Republicans and play the blame game over the defeat of health care.

In fact, he tweeted this week: "The only problem I have with" Senate Majority Leader "Mitch McConnell is that, after hearing Repeal & Replace for 7 years, he failed!

That should NEVER have happened!"

During a visit to his home state, Kentucky, McConnell joked about the limits of his power as the Senate leader with a slim majority.

SENATE MAJORITY LEADER MITCH MCCONNELL: (From video.)

You know, I'm often asked what is being the majority leader of the Senate like.

It's a little bit like being a groundskeeper at a cemetery.

(Laughter.)

Everybody's under you, but nobody's listening.

ROBERT COSTA: Complicating matters even more, the president is making a threat to shut down the government if Congress does not find federal funds to build that border wall with Mexico.

Julie, as the president goes to war with his own party, what are the costs to him and his agenda?

JULIE PACE: I think there are potential short-term costs and then potential long-term costs.

In the short term, you have to put this into the context of where we are in Washington.

We are heading into a September where there are some really big issues on the table: raising the debt ceiling, keeping the government funded - and that's before the White House even gets to the possibility of passing some kind of tax reform legislation.

And while Trump has a Republican majority in the House and the Senate, on the Senate side in particular it's pretty slim.

So if he's going to be going after members of his own party and giving them reasons to potentially vote against him, you could see that cost come pretty quickly.

And then, as you look into 2018, I look at Arizona, with Jeff Flake.

If he is really rallying behind Kelli Ward or another possible challenger to Flake, he could be putting Republicans in a position to put a weaker general election candidate on the ballot.

And if that seat were to go to a Democrat, even if the Republicans maintain their Senate majority, that margin could get slimmer.

That has long-term consequences for him.

But I also think we need to be open to the possibility that there actually are no consequences at all.

We've been in this situation with Trump before, where he does something, he goes after an ally, someone in his own party, and Republicans grumble about it, they talk tough every now and then, certainly privately, but then there are no practical consequences for him.

ROBERT COSTA: So there is this war of words, Jake, within the party, and we've seen this drama among Republicans for so long.

But on the key things they need to get done, the debt limit, will they pass a clean debt limit without anything attached and make sure the markets don't get rattled?

And will they pass a budget that funds the border wall?

Can they get those things done?

JAKE SHERMAN: I had conversations with Republicans this week who told me there's about 20 votes in the Senate and very few votes in the House for a clean debt-limit bill, and that's a big problem.

The president, according to Republicans that I talk to all the time, has not been forceful in saying what he wants.

He's not said a word about the debt ceiling.

He's not said I want a clean debt ceiling, I need a debt ceiling with strings.

For a while in his White House they were warring among themselves, and you had Steven Mnuchin and Mick Mulvaney saying completely opposite things.

They're finally on the same page.

The border wall is going to be a big fight.

And everybody on the Hill that I speak to, Republican and Democrat, believes there's going to be a shutdown either in September or in December.

ROBERT COSTA: Let's pause there because you're saying, Jake, that they may extend government funding until December, a short-term CR - that's the lingo here in Washington - to keep the government running and then maybe think about doing a border wall later on?

JAKE SHERMAN: So the government runs out of money at the end of September.

And a way to kick the can down the road and have the fight with an ending time of Christmas, which is a lot more alluring for members of Congress and will maybe help them get their act together, it's helpful for them.

So Trump is itching for a fight.

It's very clear.

He sees this as an election promise that he needs to fulfill.

He says - rightfully, he says, I ran on this.

This was a central part of my campaign, building this wall.

I think that he is going to go to the mat for this in a way that he has not gone to the mat for health care, tax reform, or any other priority.

ROBERT COSTA: But will he, Dan?

DAN BALZ: I don't know, because he blusters and he threatens and then he kind of lets it fade away.

So I think I'm waiting to see just how much he does go to war over this.

It's entirely possible that he will not do that, that he will talk tough and then he will find a way to diminish the significance of not having had it done.

ROBERT COSTA: What's the cost for the base, Dan?

With the base?

Breitbart News?

DAN BALZ: Well, that's - I mean, I think - I think - ROBERT COSTA: Stephen Bannon, his former strategist, now there.

DAN BALZ: I think that's the most important issue.

This is - you know, as Jake said - this is the rallying cry of all rallying cries.

It exceeds at his rallies "repeal and replace."

Build that wall.

We saw it again - you know, every time he does a rally, we see the chance go up.

He's not talking about Mexico paying for it anymore, obviously - (laughter) - but building that wall is still a touchstone with his base.

So I don't know how he gets out of that.

I thought it was surprising that he laid that marker down when he did and put himself now in a very, very difficult position.

ROBERT COSTA: Julie, I was thinking back to one of your interviews in the spring.

You talked to President Trump.

And he talked then about making this showdown over a border wall.

But he was able to accept a watered-down version, some security, some technology at the border.

Could we expect that again, a watered-down version of the wall?

JULIE PACE: Well, that gets to Dan's point, that we have been through these episodes before where Trump will say I will absolutely not sign something unless it has X in it - in this case, the border wall.

And then he finds a way out of it where he feels like he can still appeal to his base but doesn't have to take that drastic step to actually shut down the government.

I do think, though, that this is one of those situations where it's going to be fascinating to see how Steve Bannon operates on the outside, because he was the guy in the White House that had that whiteboard in his office.

And in talking to him and in talking to other Trump supporters who were there in the campaign, they feel like the wall is so central to this campaign promise, that it wasn't just the chants that were appealing to people during the campaign.

They really want the wall built, Trump supporters.

And so if Trump looks like he's waffling on this, I have a hard time imagining that Breitbart will be anything less than aggressive in pointing out that he's backing away from this.

DAN BALZ: I think one aspect of this is useful to remember, and that is if he fails his people and he will blame others.

ROBERT COSTA: Right.

(Laughs.)

JULIE PACE: Absolutely.

Absolutely.

DAN BALZ: He will not necessarily take the blame from his base as a result of that, because he will be able to deflect, as he's very good at doing.

ROBERT COSTA: Jake, you track Democrats.

Where are they in all this, as the president maybe tries to get a clean debt limit?

The usually wanted a clean debt limit in the past, but now it seems like they may be pushing for some concessions from Republicans.

DAN BALZ: They feel like they - this is their one chance to get something.

They're in the minority.

They're out of powers and out of ideas in a lot of ways - (laughs) - right?

I mean, they have no leverage points.

So the Obamacare subsidies, the CSR payments which help kind of stabilize insurance markets, Trump is saying he's going to stop them.

So they are going to try to insert that into the debate and try to get that tacked onto the debt ceiling.

But that presents a whole other raft of issues.

Republicans are not going to be for that.

And I just - you look at this now and you look at this kind of matrix of issues and you wonder where they're - how they're going to get out of this.

And I was texting last night with a senior Republican leadership aide in the Senate who told me: Don't worry.

We have ideas.

And I said, what are they?

And she said, no one really knows yet, but we're confident we do.

(Laughter.)

ROBERT COSTA: I think it's not just Democrats.

Let's think about the whole big moment for the Republican Party.

And the president had this bombastic, stream of consciousness rally in Phoenix on Tuesday that's really setting the tone, the pace of how everything is going to probably unfold this fall.

For 77 minutes the president rallied his base, but he did it by attacking Senators John McCain and Jeff Flake in their home state, Arizona.

He defended his comments about the violence in Charlottesville as well, painting himself as a victim of the media, claiming his words were not accurately reported.

Take a listen and you decide as we play the remarks side by side.

PRESIDENT DONALD TRUMP: (From video.)

We condemn in the strongest possible terms this egregious display of hatred, bigotry and violence.

That's me speaking on Saturday.

(Cheers.)

We condemn in the strongest possible terms this egregious display of hatred, bigotry and violence on many sides.

On many sides.

ROBERT COSTA: White House Economic Advisor Gary Cohn says he seriously considered resigning after those remarks from President Trump about that violence that left one counterprotester dead.

Cohn, who is Jewish, was standing next to the president in the lobby of Trump Tower when he said this.

PRESIDENT DONALD TRUMP: (From video.)

I think there's blame on both sides.

You look at - you look at both sides, I think there's blame on both sides.

And I have no doubt about it.

ROBERT COSTA: In an interview with The Financial Times on Friday, Cohn said: "I believe this administration can and must do better in consistently and unequivocally condemning these groups, and do everything we can to heal the deep divisions that exist in our communities."

Dan, we're seeing the president tonight with the hurricane - hopefully everyone's safe in Texas - but also his own staff.

He's facing these crises of character, crises of leadership as he approaches all the other things we're talking about on Capitol Hill.

DAN BALZ: It's a terribly delicate moment for him, because the combination of what happened and how he handled Charlottesville, and then what he did in Phoenix at that rally, has raised, you know, in a sense, fundamental questions about is he fit to be in the office.

Is he - does he have what it takes to be president?

And I think that a lot of people have made judgements about that, including people within the Republican Party.

That doesn't mean they're going to censure him or anything like that, but it makes it more difficult, even when he conducts himself presidentially, to gain back that support, to gain back that kind of trust.

It doesn't, again, mean that Republicans in Congress are going to vote against him.

They're going to vote in their self-interest.

And in many of those cases Donald Trump will be happy to sign that legislation.

But he has - he has lost something essential to being president.

And it's difficult to get that back.

ROBERT COSTA: I just want to share some breaking news tonight.

Because we're - when you think about how President Trump is going to handle this, Julie.

Joe Arpaio, the controversial sheriff from Maricopa County in Arizona, Maricopa County, he was pardoned tonight.

As the show was going to air, he was pardoned by President Trump.

And what a favorite of the base Sheriff Joe is.

And it just shows, as the president's confronting these things, he's turning to the base.

JULIE PACE: He's turning to the base.

He knows that that base is extremely loyal.

There have been some polls that show a slight weakening there, but really when you talk to folks - Trump voters and Trump supporters in the House in particular - you know, they are rock-solid with Trump.

And he knows.

He has come off a rough week with the response to Charlottesville, and the Afghanistan decision - which I know we're going to be talking about - really is unpopular with the base.

ROBERT COSTA: Why was Sheriff Joe pardoned?

He was convicted of - JULIE PACE: Well, so Trump has looked at Sheriff Joe, who took a very hard line on immigration in Arizona, and he looked at him as an early supporter who believes in what he believes in on immigration.

I do think it's worth noting, though, that it is unusual for presidents to make this type of controversial pardon at this phase of their presidency.

They usually try to send that, you know, to the back end and do it for their last couple days in office.

But to do it at this phase is really pretty extraordinary.

JAKE SHERMAN: And if you look at - the thing that's striking to me about this is if you look at how Trump treats his electoral base and how he treats his Washington base - like, he's - we're in 2017, right?

And his base right now are 535 members of Congress who will decide his presidency.

Look at what Republicans did to Barack Obama, not passing judgment about the wisdom of what they did, but they stood firm against his agenda and in a way forced him into signing a bunch of executive orders and using the executive power more than the legislative power.

This president might have to do the same, because he's angering and he's agitating against key members of his governing coalition in a way that - you know, he's treating his electoral base so well but his Washington base he's just forgetting about.

ROBERT COSTA: So why does Gary Cohn stay?

If the president continues to play to the base, if he makes these controversial comments, why does he stay, Dan?

DAN BALZ: You know, it's emblematic of so much of what we're seeing within the Republican Party today, which is great dissatisfaction with the president, disgust with some of the things he's done, a desire to see him change, and now a kind of an increasing recognition that that's not going to happen.

And yet, they're not prepared to walk away.

For whatever reason, they see self-interest in staying where they are - whether you're on the Hill working with him or whether you're in the White House working for him.

ROBERT COSTA: Julie, you run The Associated Press here in Washington, managing a lot of different reporters.

The president's attacks on the media hit a new level, or did they?

JULIE PACE: I think they did.

I think that we have to keep pointing this out.

And, look, I'm pretty clear-eyed about this.

We in the media don't have a lot of friends.

And sometimes we do ourselves a disservice by making ourselves the story here, instead of emphasizing the role that we play in our democracy and the important function that we have in our politics.

But I think we need to keep pointing this out.

I do think that if the public doesn't trust what they hear from independent news sources, that puts our democracy in a really precarious position.

And I do think this is very strategic on the president's part.

I have said this before.

I think this is as much a part of his agenda as the wall and Obamacare and tax reform, is undermining the media so that when there are negative stories about him out there, when there is really important reporting that is done, he can turn to his base and say you don't believe that.

So we need to keep doing our job, doing it fairly, doing it accurately, and reminding people that what we're here to do is to be their eyes and ears in Washington and at the White House and in Congress.

ROBERT COSTA: But, Jake, when you're on Capitol Hill, the media, again, seems to have troubled capital with voters, with readers because of some of these attacks.

JAKE SHERMAN: I will say, though, I find on Capitol Hill that members of Congress are exceedingly good to reporters, I mean in a way that even staunch Trump supporters kind of get the job that we're supposed to do and appreciate it.

And I think that's because - I don't know, I'm not going to play armchair - (laughter) - ROBERT COSTA: It's an interesting - that's true, it's a different environment on Capitol Hill versus the back and forth with the president.

Let's turn - because the president's speech in Arizona was such a high-octane President Trump, but the week began in a different way.

The president announced a recommitment of troops to Afghanistan in his first address to the nation, pledging to build up America's military presence in the region.

President Trump offered few specifics, and the move to increase troop levels is a sharp reversal for him since he called for a complete withdrawal on the campaign trail.

PRESIDENT DONALD TRUMP: (From video.)

The consequences of a rapid exit are both predictable and unacceptable.

We will not talk about numbers of troops or our plans for further military activities.

Conditions on the ground, not arbitrary timetables, will guide our strategy from now on.

ROBERT COSTA: Secretary of State Rex Tillerson offered a grim assessment of the 16-year war.

SECRETARY OF STATE REX TILLERSON: (From video.)

We believe that we can turn the tide of what has been a losing battle over the last year and a half or so, and at least stabilize the situation, and hopefully start seeing some battlefield victories on the part of the Afghan forces, who have fought very bravely but they've been fighting, I think, with less than full capabilities that we can give them.

ROBERT COSTA: Nancy Youssef, our friend, she covers the Pentagon, and joins us from Washington.

Nancy, this was a dramatic about-face for the president.

Who convinced him to change course?

NANCY YOUSSEF: Well, there were a number of factors that came into play for the president.

Remember, and as he said himself, that it's quite different when you're in office versus campaigning.

And when he came into office, he came into an Afghanistan that while a strategy wasn't yielding any definitive measures of success, there had not been any major 9/11 planned attacks from Afghanistan.

And so that, coupled with the fact that he had a general - General Nicholson, the commander in Afghanistan - asking for 4,000 troops and not, say, 30,000 troops, as President Obama confronted in 2009, allowed for an incremental increase in the troop presence there.

That, coupled with the fact that he gave greater responsibility to the Pentagon to determine the number of troops and the way that the war would be prosecuted, put sort of the burden back on the Pentagon and not just on him.

And so, from the president's perspective, it was less risky to have this incremental increase than to withdraw totally.

Had the president - ROBERT COSTA: But why the urgency, Nancy?

Why the urgency on the ground in Afghanistan?

We hear so much about ISIS in Iraq and elsewhere.

But in Afghanistan, what's the actual strength of the Taliban right now?

NANCY YOUSSEF: Well, it's grown in recent years.

They control upwards of 40 percent of the country.

They're running shadow governments not only in rural areas, as they once did and at the beginning and even just a few years ago, but in urban areas.

And in fact, we're starting to see a growing Taliban presence in the capital itself, Kabul.

And so there's a real risk that you have a Taliban overtake this very tenuous Afghan government and the Afghan forces that aren't in place to be able to protect the country on their own.

Remember that these 4,000 troops aren't going towards counterterrorism.

The bulk of them will be going towards advising and training the Afghan security forces.

ROBERT COSTA: Nancy, the president called on Pakistan to help share the burden of combatting terror in Central Asia.

Is that a realistic expectation, that Pakistan's actually going to step up and play a bigger role?

NANCY YOUSSEF: Well, from the - from the Pakistani perspective, they see the U.S. presence as part of the reason that they have to continue to shape events in Afghanistan.

That's why you have things like the Haqqani Network and members of the Taliban allowed to go back and forth in Pakistan.

The president made a very risky calculation by giving praise to India and essentially trying to pressure the Pakistanis to do more by way of giving this sort of reach out to India.

So far they have indicated that they're not onboard.

We heard from the Pakistani foreign minister today that he would be visiting his allies in China and elsewhere to try to make the case that, in fact, they are offering - what they're doing now is not contributing to terrorism, but a force of stability.

And so, so far we haven't seen it.

But we may see increased pressure from the U.S. in the form of strikes or even rhetoric that could change that.

ROBERT COSTA: Stay with us, Nancy.

Jake, real quick, to close us out - and I want to go around real quick to Dan and Julie - will Congress demand to hear more about the actual number of troops on the ground in Afghanistan?

JAKE SHERMAN: Absolutely.

I think you'll have Jim Mattis up there in the next couple weeks, and we're not going to tell you our strategy is not a thing Congress likes to hear because they cut the checks.

And they're going to say, no, you're committing U.S. troops, we're paying the bill, taxpayers deserve to know how many people are going to be there.

ROBERT COSTA: He ran as a non-interventionist, Julie.

Is he now a hawk?

JULIE PACE: I don't know if I would quite call him a hawk at this point, but certainly I think he is someone who, you know, he's not wrong, sitting in that Oval Office making these decisions is a lot different.

And I don't think he wants to be the kind of president that creates a vacuum in Afghanistan that could potentially lead that country to become a launching pad once again for a terrorism attack in the U.S. That is something that has haunted his predecessors as well.

ROBERT COSTA: Dan, Nancy mentioned all these generals surrounding the president.

Isn't it unusual in history to have these military figures in civilian roles, really shaping policy in such a widespread way?

DAN BALZ: Highly unusual in any of our memories to have this many generals playing this prominent a role in the administration.

And what's also interesting is, given all of the concerns about, you know, civilian control of the military, and now you have in a sense military control of the White House and the president.

A lot of people feel comforted by that.

They feel that these are professionals who have a duty to the country and will do the right thing if things go haywire.

ROBERT COSTA: Nancy, we have about 30 seconds left.

I was just reading Lawrence Wright's book, Looming Tower, and you look at Soviet Union 1979, so many invasions throughout history.

The president said he's not going to nation-build, he's just going to send over advisors and troops.

Is that a realistic - is that a possible goal?

NANCY YOUSSEF: Well, at this point the goal is not winning, as he states it, but to not lose.

And so I think we heard that from Rex Tillerson in his comments, that this is not about nation-building.

I think he's right about that.

But this is also arguably not about winning, it is about creating an environment such that the Taliban will be willing to come to the negotiation table, because that's how this ends.

ROBERT COSTA: That's maybe how it ends.

We'll see if it happens.

We're going to have to leave it there.

Thanks, everybody.

Thanks so much Nancy, Dan Balz, Jake Sherman, Julie Pace.

And our conversation will continue, as ever, online on the Washington Week Extra, where we'll tell you about two governors, one a Republican, the other a Democrat.

They're considering a joint independent bid for president in 2020.

I know, it's - we're going there.

(Laughter.)

You can find that later tonight at PBS.org/WashingtonWeek.

I'm Robert Costa.

Thanks for watching.

Have a great weekend.