GEOFF BENNETT: Today, two presidents known for# their fiery rhetoric toward each other met in## the Oval Office and apparently put their# acrimony behind them.

Colombia's President## Gustavo Petro has long been a critic# of President Trump and the U.S.

itself.

AMNA NAWAZ: But Mr.

Trump this afternoon# praised Petro and did not repeat previous## threats of military action.

And# in a press conference tonight,## Petro said the meeting eased tensions# between Trump and all of Latin America.

Nick Schifrin reports.

NICK SCHIFRIN: Today, at the White House, a# Colombian president who for decades criticized## what he calls American imperialism was all smiles# for the man he recently dubbed a would-be king.

President Trump greeted Gustavo Petro# warmly, offered a personal tour of what## he's labeled the Presidential Walk# of Fame and wrote Petro a letter,## "A great honor.

I love Colombia" and inscribed# his "Art of the Deal" "You are great."

DONALD TRUMP, President of the# United States: I thought he was## terrific.

He's great.

We got.. NICK SCHIFRIN: Tonight, Petro said# the meeting defused regional tensions.

GUSTAVO PETRO, Colombian President# (through translator): He gave me a## red cap that said "Make America .. and said "Make Americas Great," and that can# only be done on the basis of mutual respect.

NICK SCHIFRIN: That is a far cry# from months of mutual maliciousness.

DONALD TRUMP: Colombia is out of control, and now# they have the worst president they have ever had.## He's a lunatic who's got a lot# of problems, mental problems.

GUSTAVO PETRO (through translator): We# must respond to defend people's rights,## the rights of democracy not# to be governed by tyrannies.

DONALD TRUMP: He has cocaine mills and cocaine# factories.

He's not going to be doing it.

QUESTION: So, there will be# an operation by the U.S.?

DONALD TRUMP: It sounds good to me.

GUSTAVO PETRO (through translator): For us,## ICE operates the same .. NICK SCHIFRIN: But after the U.S.

'# -- quote -- "law enforcement action"## against Venezuelan President Nicolas# Maduro ended with him in handcuffs,## President Trump says there's# been a change in tone.

DONALD TRUMP: I mean, he's been very nice over the## last month or two.

He was certainly# critical before that.

But, somehow,## after the Venezuelan raid, he became very# nice.

He changed his attitude very much.

NICK SCHIFRIN: What hasn't changed, the# Colombian military's desire to combat drug## smuggling.

For years, they have worked# with the U.S.

to take steps like this,## interdict cocaine from Colombia# on the way to the United States.

The Trump administration's solution was military,## dozens of strikes on alleged drug boats.

Petro# described that as murder.

And his solution,## voluntary eradication, letting farmers# themselves rip up the root of the problem.

WOMAN (through translator): It# doesn't interest us.

We don't## want it because we know there's no# future or way forward there for us.

KEVIN WHITAKER, Former U.S.

Ambassador# to Colombia: The theory is not wrong.## The problem is, it's never worked in practice.

NICK SCHIFRIN: Kevin Whitaker was ambassador to# Colombia from 2014 until 2019 under Presidents## Obama and Trump.

He points out that Colombia's# cocaine production has grown year over year,## and the country now supplies nearly# 70 percent of the world's cocaine.

KEVIN WHITAKER: I mean, a serious flaw# in the Petro administration's approach## to this entire issue is to completely stop# the process of military engagement with these## illegal armed groups who# are behind the coca trade.

A serious approach would be to design# a strategy aimed at undercutting the## illegal armed groups as a military# matter.

I think that that would be## very attractive to the U.S.

administration.

I# also think it could be effective in Colombia.

NICK SCHIFRIN: Whitaker also says that,# despite historic ties, Petro and the U.S.## could cooperate on overlapping goals# with the new government of Venezuela.

The U.S.

has forced that government to# stop exporting oil to Cuba, and now,## under U.S.

pressure, Mexico could# also cut off its own supply to Cuba.

DONALD TRUMP: It's a failed nation now, and# they're not getting any money from Venezuela,## and they're not getting any money from# anywhere.

It's a failed nation.

Mexico## is going to cease sending them oil.

But we# are dealing with the Cuban leaders right now.

NICK SCHIFRIN: Since the Cuban Revolution,## the country has relied on an outside patron.

It# first lost t.. KEVIN WHITAKER: People have been predicting# the end of the Castro regime in Cuba for many,## many years.

It's hard to think that this# will be the time when it will really make## a difference.

But petroleum is# very important to the economy.## And if they lose the flows both from Mexico and# from Venezuela, that's going to hurt economically.

NICK SCHIFRIN: And Cuba and the region# will remain under enormous U.S.

pressure## that today brought a former guerrilla# fighter to the seat of U.S.

power.

For the "PBS News Hour," I'm Nick Schifrin.