President Trump apparently thought he could bluff and bluster his way out of being impeached, but he was wrong. His place of dishonor in history is now all but assured.

Speaker Nancy Pelosi’s announcement that the House will move forward with articles of impeachment was inevitable, and Trump has no one to blame but himself. No one forced him to try to strong-arm a foreign government into helping his bid for reelection. No one forced him to abuse the power of the presidency for personal gain. No one forced him to obstruct efforts by Congress to investigate his misdeeds.

Someone will force him to be held accountable, however. “Don’t mess with me,” a steely-eyed Pelosi warned a provocative reporter Thursday. Trump should have learned that lesson by now.

Three of the constitutional experts who testified before the House Judiciary Committee on Wednesday said Trump’s Ukraine shakedown scheme and his obstruction of Congress clearly are impeachable offenses. The fourth expert, handpicked by Trump’s Republican defenders, said the president’s actions only might be impeachable, pending the collection of more evidence. None said Trump’s dealings with Ukraine were “perfect,” as Trump ridiculously claims.

So now Pelosi’s committee chairmen will begin drafting one or more articles of impeachment, which the House is expected to vote on within weeks, perhaps even before Christmas. Barring some surprise on the order of an asteroid strike, Trump will become just the third president in U.S. history to be impeached and face trial in the Senate.

Would it be better, if possible, to first hear more testimony and gather more evidence? Of course it would.

We should hear from acting White House chief of staff Mick Mulvaney, who appears to have been instrumental in Trump’s ploy to coerce Ukraine into manufacturing dirt on Joe Biden by withholding $391 million in military aid. We should hear from former national security adviser John Bolton, who reportedly called the whole thing a “drug deal” and said he wanted nothing to do with it. We should hear from Secretary of State Mike Pompeo and former energy secretary Rick Perry, who were “in the loop,” according to witnesses. We should hear from Trump’s personal lawyer, Rudolph W. Giuliani, though at this point I suspect he might respond under oath by invoking the Fifth Amendment.

Congress should be able to examine all the documents it has requested and subpoenaed. Investigators should have the opportunity to see for themselves whether Trump’s supposed high-minded interest in rooting out corruption in Ukraine was genuine or whether it was cobbled together after the scheme was discovered to create some kind of fraudulent paper trail.

But Trump won’t let any of those officials testify and won’t produce any of the documents Congress has demanded. Appealing to the courts to force the administration to comply would take months — and would play into Trump’s hands. Congress cannot allow him to run out the clock.

Clearly, there is urgency. Trump was seeking foreign interference, on his behalf, in the coming election. If he is not impeached, does anyone doubt he will keep trying? Giuliani traveled to Ukraine and Hungary this week and reportedly met with allegedly corrupt former prosecutors. Incredibly, they’re still at it.

Would it be better if at least some Republicans had the courage to defend the Constitution rather than blindly follow Dear Leader Trump? Absolutely. But though naked political power can compel loyalty from the craven, it cannot change the facts — or absolve the House of its responsibility.

The consensus view is that there is virtually no chance Trump will be removed from office by the Senate. It is possible that dramatic new evidence will emerge or reluctant witnesses will decide to testify. No one knows how big a role Chief Justice John G. Roberts Jr., who will preside, might take in shaping the proceedings. But we must acknowledge that medical science has not yet invented a drug that can make Republican senators grow spines.

So be it, then. Some people believe it would help Trump politically to be impeached, subjected to a trial and ultimately acquitted. I disagree; I think “Impeached but Not Removed” is a pretty lousy campaign slogan. At this point, however, political fallout must take a back seat to constitutional duty.

“Our democracy is what is at stake,” Pelosi said Thursday. “The president leaves us no choice but to act, because he is trying to corrupt, once again, the election for his own benefit.”

Impeachment is something “which I wish the president had not made necessary,” Pelosi said. And she’s right. Trump is impeaching himself.

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