AMNA NAWAZ: European leaders have widely condemned## those comments by Mr. Trump# as reckless and dangerous.

And in a meeting focused on Ukraine today,# Germany, France, and Poland express solidarity## with one another, saying Europe must be# ready to defend itself and its allies.

For more on the implications# for the U.S. and the world,## we turn now to Kurt Volker.

He was U.S. ambassador# to NATO during the George W. Bush administration## and U.S. special representative for Ukraine# negotiations during the Trump administration.

Ambassador Volker, welcome, sir.# Thank you so much for joining us.

KURT VOLKER, Former U.S. Special Representative# for Ukraine: Thank you for having me.

AMNA NAWAZ: I want to begin with your reaction#.. saying he would encourage Russia to attack# a NATO ally if they didn't pay their dues.

What did you think when you heard that?

KURT VOLKER: It's really an outrageous comment.

I mean, if you look at what Russia is doing to# Ukraine right now, killings, bombing cities,## civilians, civilian deaths, torture, rape as# a weapon of war, you shouldn't wish this on## anybody.

And to say that we would encourage Putin# to attack one of our allies is really too much.

Now, to be clear, what President Trump# was doing, he was at a campaign rally,## and he was bragging about having said# this in the past.

It wasn't a comment## about the future.

But even so, it is# nothing to brag about.

It is not the## kind of leadership that America# should be showing in the world.

And I would add that NATO was created to# prevent war.

NATO was created so that,## by banding together and countries# pledging to defend each other,## we would dissuade anybody from attacking.

And here# we have a suggestion that someone should attack.## That's exactly the opposite of what we should# be trying to do.

We don't want to see a war.

AMNA NAWAZ: What do you believe# that the U.S. relationship with## NATO would look like under# another Trump presidency?

KURT VOLKER: Well, it's hard to know,# because President Trump says a lot of things.

Remember, during the first -- President# Trump's first term as president, he had## a lot of warm words for Vladimir# Putin, and, at the same time,## he threw the Russian Consulate out of San# Francisco.

He provided arms for Ukraine.## He rounded up and arrested and deported# a lot of Russian intelligence officers.

So there are things that were done under the# Trump administration that were sound policy,## even though the rhetoric coming from the# president sometimes is in the opposite direction.

AMNA NAWAZ: Do you believe# that he would try to pull## the U.S. out of the alliance, as he said he would?

KURT VOLKER: I don't know.

The most recent thing he said, that I heard#.. in kind of a dormant position.

I don't# know what that means.

NATO is a defensive## alliance and is, by definition, almost# in a dormant position until attacked.

But the point is that, if attacked, there# needs to be a certain and substantial response,## so that it serves its role of deterring such an# attack.

And I think that he would be unlikely to## try to pull the U.S. out of NATO.

And even# if he tried, I think it would be unlikely## to be successful, because there would be# substantial resistance within the Senate.

And it would certainly go to the courts to see# whether he even had the authority to do that.

AMNA NAWAZ: Ambassador, I want to put to# you a statement from Trump senior adviser## Jason Miller in response to some of the# coverage around Mr. Trump's comments.

He said this in part.

He said: "Democrat and# media pearl-clutches seem to have forgotten## that we had four years of peace and prosperity# under President Trump, but Europe saw death and## destruction under Obama/Biden and now more# death and destruction under Biden.

When## you don't pay your defense spending, you# can't be surprised that you get more war."

Ambassador, his claim is basically that, because# President Trump publicly pressured people to## increase their defense spending, the world# was safer.

What do you make of that argument?

KURT VOLKER: Well, there are several things## that are wrapped up there and I# think we have to..

The first thing is that he's absolutely# right.

European allies do need to spend## more on defense.

Every U.S. president that I# have worked with ever since Reagan has said## European allies need to do more on defense.# President Trump was more direct about it,## more forceful about it, and allies did# spend more on defense under his watch,## but they have spent even more under President# Biden, and it's not because of Biden.

It's because of Putin.

Putin is -- has# launched a war in Europe the likes of## which we have not seen since World War II, and# this has caused European allies to genuinely## fear for their security and to begin doing much# more for defense than they had been.

Poland is## going to spend 4 percent of GDP on defense this# year, 40 billion euros, Estonia also 4 percent.

These countries are ramping up their# defense spending because of what they## see happening in Europe, and that's# why it's so important that the U.S.,## as the leader of NATO, be supporting and# encouraging that and sending a message to## any aggressor that there would be# a collective response if attacked.

AMNA NAWAZ: Before we go, I need to ask you,# Ambassador, about the immigration piece of## Mr. Trump's plans that my colleague# Laura Barron-Lopez just reported on.

The idea that a U.S. president# says he would deploy red state## National Guard troops to go into blue# states to remove undocumented migrants,## what's your reaction to that?

What would# be the impact of something like that?

KURT VOLKER: Well, let's first say I don't think# that this is something that's actually possible.

The governors and the National Guards of the# states where this would take place would not## want this.

They would resist it.

I can't# see states going to put their militias up## against each other.

This would be a civil# war.

I really don't see this happening.

AMNA NAWAZ: That is former U.S. Ambassador# to NATO Kurt Volker joining us tonight.

Ambassador, thank you so much# for your time.

Appreciate it.

KURT VOLKER: Thank you.