WASHINGTON — President Donald Trump's worlds collided in devastating fashion in Washington on Friday, exposing legal and political vulnerabilities that Democrats want to exploit as he works to survive impeachment and his 2020 re-election bid.

All three branches of government demonstrated, in one day and in unmatchable high-profile fashion, the cost Trump and his loyalists have been willing to impose on the nation and its citizens — including members of his inner circle at times — in pursuit of political and personal aims. And ultimately, those costs are at the heart of the argument Democrats will make for ousting Trump, one way or the other.

"The powers of the presidency are immense, but they are not absolute and they cannot be used for corrupt purpose," House Intelligence Committee Chairman Adam Schiff, D-Calif., said on Friday. "The American people expect the president to use the authority they grant him in service of the nation, not to destroy others to advance his personal or political interests."

Inside a Capitol Hill hearing room, a veteran diplomat testified before the Intelligence Committee and the nation that Trump abused his power by smearing her so that he could, in subversion of American interests, facilitate a deal with Ukraine that would likely help his campaign.

At the same time, a mile and a half away from Capitol Hill at the White House, Trump again tried to discredit former Ukraine Ambassador Marie Yovanovitch as she recounted how the president and his loyalists had damaged those interests, hurt morale at the State Department and tried to sully her reputation, which lawmakers in both parties agreed was stellar.

And before Yovanovitch was done testifying, at a federal courthouse between the Capitol and the White House, a jury convicted longtime Trump political adviser and self-described dirty trickster Roger Stone of lying to Congress and witness tampering in covering up his efforts to coordinate with WikiLeaks, which released a trove of stolen emails to help Trump win the 2016 election.

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"The chickens are finally coming home to roost for the Trump presidency," said Neera Tanden, president of the liberal think tank Center for American Progress and a onetime aide to Barack Obama and Hillary Clinton. "The events of today — the ambassador's testimony, Trump's disgusting smears, and the Roger Stone conviction — all point to a man who sought Russia's interference to win in 2016, tried to cheat to win in 2020 and victimized people who stood in his way."

Under questioning from Schiff and the committee Democrats' lawyer, Yovanovitch recounted how she was yanked from her post as ambassador in May and told to get on the next flight home, how she learned about Trump allies smearing her in Ukraine and how she felt when she found out through the subsequent release of a summary of a Trump call with Ukrainian President Volodymyr Zelenskiy that her own nation's leader had said she was "bad news" and was going to "go through some things."

"I was shocked and devastated," she said in testimony that reflected what she had previously told the committee behind closed doors.

Her crime, according to Yovanovitch and others who have testified in the inquiry: She was known for fighting corruption, and she was stationed in a country where by-the-book governance would have made it difficult for Trump to leverage American power to secure publicly announced investigations into leading political rival Joe Biden and foreign interference in the 2016 election.

Yovanovitch, who spoke in tones so soft that audience members had to listen closely to hear her, was a sympathetic enough figure in her own right that the cross-examination of her by Republican counsel and lawmakers was decidedly deferential — particularly with regard to her credentials as a career public servant.

But that's not how Trump behaved toward her.

A few minutes after 10 a.m. he fired off a pair of tweets in her direction.

"Everywhere Marie Yovanovitch went turned bad. She started off in Somalia, how did that go? Then fast forward to Ukraine, where the new Ukrainian President spoke unfavorably about her in my second phone call with him. It is a U.S. President’s absolute right to appoint ambassadors," Trump wrote in the first tweet.

Not long after that, Schiff read Trump's remarks to Yovanovitch and asked her whether they were meant to intimidate her.

She said she couldn't speak to the president's motive, but that "the effect is to be intimidating."

Schiff replied that he and other lawmakers take witness intimidation "very, very seriously" — hinting that Trump may have committed an impeachable offense in the midst of an impeachment inquiry.

Wyoming Rep. Liz Cheney, the No. 3 Republican in the House and a former State Department official, admonished Trump.

"I don't think the president should have done that," she said of the tweeting.

The question lawmakers of both parties asked Yovanovitch to answer was whether Trump had the power to just remove her from office at will.

"All the president has to do is say he wants a different ambassador," she said at one point.

Republicans wanted her to say that to show that there was nothing corrupt about pulling her from the country, and Democrats thought it demonstrated the smear campaign he and his allies ran to discredit her and set up a diplomatic back-channel was evidence that he abused that power.

The question that remained at the end was why Trump felt the need to try to destroy Yovanovitch's credibility.

"All we have is our reputation," she said.