Washington — What would a president have to do, hypothetically, to get this Congress to impeach him?

Obstruct a Justice Department investigation, perhaps? No, apparently that’s not enough. What about playing footsie with a hostile foreign power? Abusing his office to settle personal grievances? Using instruments of the state, including the justice system, to attack his perceived political opponents? Aligning the nation with murderous foreign dictators, while forsaking democracy and human rights? Violating campaign-finance laws with disguised hush-money payments to alleged paramours? Giving aid and comfort to neo-Nazis and white supremacists? Defying requests and subpoenas from congressional committees charged with oversight? Refusing to protect our electoral system from malign foreign interference? Cruelly ripping young children away from their asylum-seeking parents? Lying constantly and shamelessly to the American people, to the point where not a single word he says or writes can be believed?

President Trump has done all of this and more. If he doesn’t warrant the opening of an impeachment inquiry, what president ever would?

The message that special counsel Robert Mueller delivered on Wednesday was clear. Keeping scrupulously within the bounds of his 448-page report, he took pains to highlight three points: If the evidence had shown that Trump was innocent of obstruction of justice, the report would have said so. Mueller believed, however, that he had no authority to charge Trump with a crime. And “the Constitution requires a process other than the criminal justice system to formally accuse a sitting president of wrongdoing.”

That process, like it or not, is impeachment. I’ve been back and forth on the wisdom of taking that step, but there’s one question that nags me: If the impeachment clause of the Constitution wasn’t written for a president like Trump, then why is it there?

Let me acknowledge that House Speaker Nancy Pelosi’s policy of disciplined restraint has been, so far, a political success. With an eye toward the 2020 election, some Democrats can fire up the base with impeachment calls while others — especially House members in districts Trump won — can talk about bread-and-butter issues as if the nation were engaged in a normal policy debate.

Trump’s approval numbers have been falling. I’m not sure about Pelosi’s theory of Trump’s mindset — that he is trying to bait Democrats into impeachment, knowing he would be acquitted by the GOP-controlled Senate and would then have more credible claims of exoneration and victimization. But I admit that Pelosi could be right.

She could be wrong, though. Trump’s going to claim “no collusion, no obstruction” anyway, and he’ll say that if Democrats really thought he had committed a crime, they’d have the guts to impeach him.

And if there’s one thing everyone should know about Trump by now, it’s that he will remain on the offensive. Mueller seemed to throw him temporarily off his stride — the president responded Wednesday with a limp tweet about how there was “insufficient evidence and therefore, in our Country, a person is innocent.” But by Thursday morning, Trump was portraying himself as the victim of the “Greatest Presidential Harassment in history” and blasting Mueller, a rock-ribbed Republican, for an alleged — and imaginary — conflict of interest.

With the help of Attorney General William Barr, Trump is going to keep pushing the bogus narrative that the entire investigation of his campaign’s ties to Russia was some kind of “witch hunt” or even an “attempted coup.” Senate committees will give this ridiculous conspiracy theory a measure of official sanction, and the right-wing media machine will trumpet it far and wide.

House committees, meanwhile, are being stonewalled. Trump may ultimately lose court battles over the documents and witnesses he is withholding, but that will take time — and Democrats’ focus, meanwhile, will be on process rather than on the substance of Trump’s misdeeds.

So I don’t think the political calculus is at all clear. The moral calculus is a different story.

In myriad ways — beyond those illuminated by Mueller — Trump has disgraced the office of president and sullied the nation’s honor. He’s not a disrupter; he’s a destroyer who tears institutions down and obliterates hallowed ideals with no interest in replacing them — no interest at all, really, except self-interest.

The Trump era will end someday, and we’ll all have to account for what we did, or failed to do, to fight for our nation’s soul. Mueller gave our elected representatives in Congress a clear road map for holding Trump accountable. Ten years from now, even one year from now, I wonder what we’ll think of those who decided not to take even the first step.

— Eugene Robinson is a columnist for Washington Post Writers Group.