WASHINGTON – Exactly what could overshadow a nuclear summit between a U.S. president and a North Korean despot?

House oversight hearings on Capitol Hill managed to cross that high bar Wednesday with testimony from Michael Cohen, President Trump's former fixer, detailing what he described as bank fraud, hush money payments, racist chatter, perjury and more by his one-time boss. His explosive 30-minute opening statement was followed by hours of sometimes-combative exchanges over Trump's conduct and Cohen's credibility.

That said, it's not clear whether the litany of lies and unsavory behavior – some of it criminal, if true – will significantly sway voters' attitudes toward Trump, including whether he deserves to be impeached now, say, or re-elected next year.

Because up until now, nothing has.

Trump's presidency has had several unprecedented characteristics, one of them being the steadiness of his support. His job-approval rating has bumped between 35 and 45 percent in The Gallup Poll since the day he was inaugurated. Unlike his predecessors, not even record low unemployment has won him much support from his skeptics. And not even missteps such as the record-setting government shutdown has cost him much allegiance among his believers.

The five-minute segments for members of the House Oversight and Reform Committee to question or speechify mirrored that polarization. Just about every Democrat posed questions meant to illuminate the worst allegations against Trump. Almost every Republican pressed reasons not to believe Cohen, who is on his way to prison for lying to Congress and other felonies.

Many of the allegations he made were familiar from news accounts over the past year, typically based on unnamed sources. What made this day different, and notable, was that Cohen was speaking on the record, and under oath, and with the perspective of a close aide who had once declared he would "take a bullet" for his boss.

Cohen, 52, looked tense and exhausted, but he generally spoke with a calm and emphatic tone. He began by apologizing, expressing regret for his willingness to do Trump's dirty work and for lying to Congress. He described a life and a livelihood now turned upside down. Worried about attacks, he said he now insists that his wife and children walk ahead of, not beside, him when they go out.

One of the few times he openly bristled was when Rep. Jim Jordan, R-Ohio, accused him of lacking remorse.

"Shame on you, Mr. Jordan!" Cohen shot back. When another Republican, Rep. James Comer of Kentucky, noted that Cohen had called Trump a "cheat" and asked what he would call himself, he replied quietly, "A fool."

Indeed, Cohen denied some of the wilder speculation that has circulated about Trump. He said he didn't know if there was a "love child" in the president's past. He said he didn't believe rumors about an elevator video that allegedly showed Trump hitting his wife, Melania.

But the portrait Cohen painted of Trump was damning. He called the president a bully, a liar, a racist, a con man. He testified that Trump submitted inflated financial statements to Deutsche Bank when he was applying for a loan. He said Trump lied when he denied under oath knowing a businessman with alleged Russian mob ties.

As a presidential candidate, despite his denials, Trump knew in advance – via adviser Roger Stone – that Wikileaks was going to unload a "massive dump" of hacked Democratic emails, Cohen said. While he was president, Trump told Cohen to lie to reporters about whether he knew about money being paid to buy the silence of an adult film star about an alleged sexual encounter, a payment that prosecutors say would be an illegal campaign contribution.

Cohen brought along a copy of a check for $35,000 signed by Trump, from his personal account, which Cohen said was a partial reimbursement of those payments.

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"He has both good and bad, as do we all," Cohen said. "But the bad far outweighs the good, and since taking office, he has become the worst version of himself."

The day-long hearing included some of the most serious allegations ever made by a former aide against a sitting president at a congressional hearing, though there have been others.

During the Iran-contra hearings in 1987, National Security Council staffer Oliver North testified that President Reagan knew North was diverting funds from secret Iran arms sales to the Nicaraguan contras. During the Watergate hearings in 1973, fired White House counsel John Dean implicated President Richard Nixon in the conspiracy to cover up the scandal. Those hearings prompted Nixon to resign from office in the face of all-but-certain impeachment.

This time, whatever the impact of Cohen's testimony, the hearing sets the stage for the forthcoming report from special counsel Robert Mueller – and the former FBI director who has led the inquiry into Russian meddling in the 2016 election doesn't have the credibility issues that opened Cohen to attack.

Meanwhile, in Hanoi, Trump was embracing Kim Jong Un at what the White House hoped would be a triumphant display of nuclear diplomacy – perhaps something so dramatic it would reclaim the headlines.

For now, though, the loudest explosions were political, and back home in Washington.

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