The second impeachment of Donald Trump was an improvement, but only a partial and halting one, over the first impeachment. When he was impeached in 2020 for obstruction of Congress and abuse of power in the Ukrainegate affair, the dividing line was almost entirely partisan. All Republicans in the House of Representatives rejected impeachment while all but three Democrats voted to impeach. The Senate was also divided on partisan lines, with Mitt Romney the only one to break ranks as the first senator to vote to convict a president of his own party.

Romney’s stance was a lonely one then; this time, he has more company. In the 2021 impeachment over Trump’s “incitement of insurrection,” 10 Republicans in the House voted to impeach and seven Republican senators voted to convict. The first impeachment ended with 48 senators voting to convict, 52 to acquit. In the sequel, the result was a 57-43 conviction vote, a strong majority—but still far short of the high hurdle of 67 required by the Constitution. Even though Trump was acquitted, a robust majority of the Senate voted for his conviction. The growth of the opposition to Trump from the first to the second Senate vote is a mark of his slowly weakening hold on the Republican Party.

It’s essential to focus on the partisan breakdown of the vote, because impeachment is a political process, not a legal one. In the two impeachments, Trump’s lawyers worked diligently to muddy the waters by saying that the impeachment process was unfair because it didn’t observe the rules of criminal or civil courts. This was pure smoke and mirrors. The punishments meted out by impeachment (removal from office and/or disqualification from future high office) are political penalties. The process is meant to deal with a fundamentally political question: who is qualified to hold high office.

The two impeachments make sense only if we see them as part of a bipartisan political project shared by almost all Democrats and a minority of Republicans: the attempt to de-Trumpify American politics. Trump is a toxic figure on many grounds (racism, corruption, abuse of office, and incitement to violence). His sway over millions of followers, making up a majority of Republicans, is dangerous and destabilizing.

American politics can return to health only if Trump’s political power is radically diminished. The still-urgent mission is to turn Trump into a political pariah, to ostracize him from the political process, to change the incentive structure so that Republicans will think twice before allying themselves with Trump.

The failure of both impeachments to end in a conviction is disappointing, especially given the weight of evidence. In the second trial, Representative Jamie Raskin was a particularly effective impeachment manager. Raskin and his colleagues did a superb job laying out Trump’s repeated incitement of violence and attempts to overturn the election. The biggest misstep was the uncertainty about calling witnesses. Initially witnesses were ruled out, but then on Friday night, with the release of a startling official statement from Republican Representative Jaime Herrera Beutler, there was a push to hear from witnesses.

Alas, the House impeachment managers backed down, likely under pressure from Senate Democrats and the White House, both eager to wrap up the trial quickly. Delaware Senator Chris Coons, almost certainly acting as Joe Biden’s emissary, put the screws on the impeachment managers. According to Politico, Coons told House Democrats, “The jury is ready to vote. People want to get home for Valentine‘s Day.”

The truncated trial was a grievous mistake. Democrats gave up a chance to highlight testimony that would surely have embarrassed Trump and his supporters—and may even have pried loose a few more Republican senators. Still, in the larger project to ostracize Trump, even a foreshortened impeachment and trial serves a purpose.

The two impeachments were the first baby steps. The next moves have to be legal remedies (through both criminal and civil courts) as well as continued congressional investigation to establish the facts about the January 6 riot. There is some tension between these two goals: Care has to be taken that the gathering of evidence for a congressional investigation doesn’t taint any court proceedings.

Republican Senator Bill Cassidy of Louisiana, who voted to convict, has called for a full-scale investigation into the January 6 riot. “I think there should be a complete investigation about what happened on Jan. 6,” Cassidy told ABC News. “Why was there not more law enforcement, National Guard already mobilized, what was known, who knew it, and when they knew it, all that, because that builds the basis so this never happens again in the future.” House impeachment manager Representative Madeleine Dean, Senator Coons, and Nancy Pelosi have all proposed that this investigation be a 9/11-style truth commission.

This sort of commission would be a mistake. Commissions of this sort often serve to whitewash the truth in the interest of elite comity. The 9/11 commission notoriously kept classified for more than a decade information about the support for terrorism by Saudi Arabian officials. Even now, some of this information remains redacted. A congressional investigation would be much more transparent, much more inclined to probe deeply, and much more in keeping with the Constitution.

With the proper timing, both the courts and Congress can continue the necessary work of documenting Trump’s criminal behavior. Taking these actions will be difficult, since there will be constant calls to move on in the interest of national unity. But true national unity requires that Trump’s crimes be documented and punished.

The main worry with a congressional investigation is that it might inadvertently taint any criminal investigation. But if court cases start documenting presidential criminality, this will clearly become a political as well as a legal matter. The model here should be the robust congressional investigations of the 1970s that arose in the wake of Watergate such as the Church Committee’s investigation of the CIA and other government agencies. These investigations should work to produce a clear record of Trump’s crime and the failures of the political system that enabled him. This is America’s best chance of a lustration.

The two impeachments were just the first halting and limited efforts at holding Trump accountable. There is much more work still to be done. Democrats and their allies among Republicans need to keep their eyes on the prize: The goal is to turn Trump into a political nomad, friendless and homeless. That’s the only way to achieve the necessary de-Trumpification of America.