WASHINGTON — Ralph Waldo Emerson seemed to foresee the lesson of the Senate impeachment trial of President Trump. “When you strike at a king,” Emerson famously said, “you must kill him.”
Mr. Trump’s foes struck at him but did not take him down.
With the end of the impeachment trial now in sight and acquittal assured, a triumphant Mr. Trump emerges from the biggest test of his presidency emboldened, ready to claim exoneration and take his case of grievance, persecution and resentment to the campaign trail.
The president’s Democratic adversaries rolled out the biggest constitutional weapon they had and failed to defeat him, or even to force a full trial with witnesses testifying to the allegations against him. Now Mr. Trump, who has said that the Constitution “allows me to do whatever I want” and pushed so many boundaries that curtailed past presidents, has little reason to fear the legislative branch nor any inclination to reach out in conciliation.
“I don’t think in any way Trump is willing to move on,” said Mickey Edwards, a former Republican congressman who teaches at Princeton University. “I think he will just have been given a green light and he will claim not just acquittal but vindication and he can do those things and they can’t impeach him again. I think this is going to empower him to be much bolder. I would expect to see him even more let loose.”
Impeachment will always be a stain on Mr. Trump’s historical record, a reality that has stung him in private, according to some close to him. But he will be the first president in American history to face voters after an impeachment trial and that will give him the chance to argue for the next nine months that his enemies have spent his entire presidency plotting against him to undo the 2016 election.
“This was clearly a political coup d’état carried out by a group of people who were amazingly, openly dishonest and I think it’s going to be repudiated,” said former Speaker Newt Gingrich, a strong ally of the president’s. “He’s been beaten up for three solid years and he’s still standing. That’s an amazing achievement if you think about it.”
Even before a final vote on the impeachment charges on Wednesday, Mr. Trump has several high-profile opportunities in the next few days to begin framing the new post-trial environment to his advantage.
On Sunday, he will be interviewed by Sean Hannity of Fox News during the pregame of the Super Bowl, one of the most watched television events of the year. Then on Tuesday, he will deliver his State of the Union address from the dais in the House chamber where he was impeached in December.
A senior administration official briefing reporters on Friday said the president will use his State of the Union address to celebrate “the great American comeback” and present “a vision of relentless optimism” encouraging Congress to work with him. Mr. Trump plans to pursue an agenda of cutting taxes again, bringing down prescription drug prices, completing his trade negotiations with China and further restricting immigration.
From there, Mr. Trump will head back to the campaign trail, starting with a rally in New Hampshire on Feb. 10, the night before the state’s first-in-the-nation primary race, an effort to upstage the Democrats as they try to pick a nominee to face him in the fall.
Democrats insist that Mr. Trump has been damaged by the evidence presented to the public that he sought to use the power of his office to illicitly benefit his own re-election chances. Even as they line up to acquit him, some Senate Republicans have acknowledged that the House managers prosecuting the case proved that Mr. Trump withheld $391 million in security aid to Ukraine as part of an effort to pressure it to announce political investigations into his domestic rivals.
But the public comes out of the impeachment trial pretty close to where it was when it started, divided starkly down the middle with somewhat more Americans against Mr. Trump than for him.
When the House impeached him in December, 47.4 percent supported the move and 46.5 percent opposed it, according to an analysis of multiple surveys by the polling analysis site FiveThirtyEight. Now as the trial wraps up, 49.5 percent favor impeachment versus 46.4 percent who do not.
Those numbers are strikingly close to the popular vote results from 2016, when Mr. Trump trailed Hillary Clinton 46 percent to 48 percent even as he prevailed in the Electoral College. That means that the public today is roughly where it was three years ago; few seem to have changed their minds. And the president has done nothing to expand his base and by traditional measures is a weak candidate for a second term, forcing him to try to pull the same Electoral College inside straight he did last time.
Mr. Trump is the only president in the history of Gallup polling who has never had the support of a majority of Americans for even a single day, a troubling indicator for re-election. Nine months is an eternity in American politics these days and, given his history, Mr. Trump could easily create another furor that will change the campaign dynamics, the economy could become an issue, and with all the accumulated allegations some analysts anticipate a certain scandal fatigue could weigh him down.
But Mr. Trump is gambling that he can rally his most fervent supporters by making the case that he was the victim and not the villain of impeachment while keeping disenchanted supporters on board with steady economic growth, rising military spending and conservative judicial appointments. He has made clear he will paint former Vice President Joseph R. Biden Jr. as corrupt if he faces him in the fall and will assail other possible Democratic challengers as socialists.
If Mr. Trump does win a second term, it would be the first time an impeached president had the opportunity to serve five years after his trial and Mr. Trump’s critics worry that he would feel unbound. He has already used his power in ways that presidents since Richard M. Nixon considered out of line, like firing an F.B.I. director who was investigating him and browbeating the Justice Department to investigate his political foes.
While in theory nothing in the Constitution would prevent the House from impeaching him again, as a political matter that seems implausible given that he has demonstrated his complete command over congressional Republicans led by Senator Mitch McConnell of Kentucky, leaving the president less to fear from a Democratic House. Some House managers warned that acquittal would lower the bar for presidential misconduct, meaning that Mr. Trump would feel even freer to use his power for his own benefit because he got away with it.
“He is going to ratchet it up to another level now,” said Anthony Scaramucci, the onetime White House communications director who has broken with Mr. Trump. “He’s going to be Trump to the third power now. He’s not going to be exponential Trump because that’s not enough Trump. It’s going to be Trump to the third power.”
But in that, Mr. Scaramucci said, are the seeds of Mr. Trump’s own downfall because he could go so far that he finally alienates enough of the public to lose. “The one person who absolutely can beat Trump is Trump,” he said.
No other impeached president had the opportunity or challenge that Mr. Trump does. President Andrew Johnson, who was acquitted in 1868, was a man without a party, a Democrat who had joined the Republican Abraham Lincoln’s ticket, and was so disliked that both parties nominated other candidates shortly after his Senate trial, leaving him to finish his last 10 months in office a lame duck.
Indeed, while Johnson was not removed from office, impeachment reduced him to a shadow president, said Brenda Wineapple, author of “The Impeachers,” an account of his trial.
“The Republicans still had a majority in Congress so they could reject some of his appointments, which they did, and override his vetoes of their legislation — and they could allow the states that conformed to the Reconstruction Acts to re-enter the Union,” she said. “So in that sense, Johnson was hamstrung, if not powerless.”
President Bill Clinton was in his second term when he was impeached and acquitted, never to be on a ballot again. With nearly two years left in office, he tried to move on from his impeachment, all but pretending it had not happened. On the day of his acquittal in 1999, he appeared in the Rose Garden alone and expressed regret rather than vindication.
“I want to say again to the American people how profoundly sorry I am for what I said and did to trigger these events and the great burden they have imposed on the Congress and on the American people,” Mr. Clinton said, calling for “a time of reconciliation and renewal.”
As he turned to leave, a reporter called after him. “In your heart, sir, can you forgive and forget?”
Mr. Clinton paused as if deciding whether to take the bait, then turned and answered, “I believe any person who asks for forgiveness has to be prepared to give it.”
Mr. Clinton, who unlike Mr. Trump admitted wrongdoing without agreeing that he committed felonies, never truly forgave his opponents, or reconciled with them, but for the most part he avoided expressing those feelings publicly.
“Clinton saw the acquittal as a humbling end to that chapter and I think Trump sees it as a way to start his re-elect,” said Jennifer Palmieri, who was a top aide to Mr. Clinton. “He just wanted to shut the door on that and move on and have a fresh start. And Trump sees it as a jump start — ‘this is what I’m going to run on.’”
Mr. Clinton had some help in that Republicans themselves emerged from his trial feeling bruised by their failure to remove him and the clear public repudiation of the impeachment in polls and the midterm elections. Unlike Mr. Trump, whose approval ratings remain mired in the mid-40s, Mr. Clinton’s popularity reached its highest level during impeachment, with 73 percent of the public backing him just days after the House charged him with high crimes.
“I don’t think Clinton was emboldened. I think he was embarrassed about the mess he caused and he wanted to somehow move on and fix his own reputation,” said John Feehery, a Republican strategist who was a top adviser to Speaker J. Dennis Hastert at the time.
And so did the Republicans. “I think both the president and the speaker had a vested interest in moving past impeachment to getting things done,” he said. “We were very conscious about how polarizing impeachment was and we were dedicated to healing the country and repairing the G.O.P. brand.”
That does not seem like the likeliest path forward for Mr. Trump, more of a pugilist than a peacemaker. “He’s obviously legitimately pretty angry,” said Mr. Gingrich, who was forced out as speaker after Republicans lost the midterm elections during the drive to impeach Mr. Clinton. “Given that he’s a natural counterpuncher, he may decide to go after them.”
“That’s not his best strategy,” Mr. Gingrich said. “His best strategy is to assume that the Democrats are totally out of control, that they will not be able to keep fighting. If he appears conciliatory, they’re going to very badly damage themselves with average voters who are going to say these guys are pathological.”
“He has that option,” he added. “I’m not saying he’s going to take it.”