We're heading for impeachment. Today a group of seven prominent freshmen Democrats representing swing districts published an op-ed in The Washington Post calling for President Trump's impeachment if allegations that he blackmailed the president of Ukraine for dirt on the Democratic frontrunner Joe Biden and his son Hunter turn out to be true. These are the very members that House Speaker Nancy Pelosi (D-Calif.) had crafted her 2020 strategy to protect, and it took only a few hours for her to announce the opening of a formal impeachment inquiry. It was as if a couple staying together for the sake of the children gets sat down by the kids themselves and told to go ahead and get a divorce.

What caused this dramatic shift in the position of Democrats who had, only the week before, seemed bent on holding the activist base at bay and playing it safe through next November? It could be the seriousness of the alleged misconduct. And make no mistake: If President Trump really did hold up aid to Ukraine to extract damaging information about the Bidens, it would arguably be the most mind-bogglingly corrupt thing he's done in office.

And it could be, as the hawkish Rep. Abigail Spanberger (D-Va.) and her colleagues argued in their op-ed, that their volte face is about the "national security threat" that these allegations represent. But is extorting the president of Ukraine worse than casually threatening nuclear annihilation on Twitter? Your mileage may vary, I guess, but it seems more likely that Democrats believe they will have more luck making charges against Trump stick, both in the inquiry itself and in the court of public opinion, if they involve an unfolding scandal that bears directly on the 2020 election.

For months, as pressure from activists and left-leaning thought leaders has grown, it has been clear that Pelosi thinks President Trump is so unpopular as it is that Democrats can beat him, hold the House, and perhaps even nab the Senate. This is not an unfounded hope — at Real Clear Politics, analyst Sean Trende's simulations suggest the GOP would be expected to lose the Senate if Trump is at 42 percent job approval or worse, a number he has managed to plunge past multiple times during his desultory presidency. If the ship is sailing toward victory, so this thinking goes, don't knock it off course when a majority of the public still opposes impeachment.

While I happen to disagree, there is a certain logic to their position. At this point, the events of the Russia scandal are mostly years in the rearview. And while the wrongdoing detailed in the Mueller Report is just as serious, if not worse, than the new Ukraine scandal, for most ordinary voters it's old news. The president's gambit to hire a pliable attorney general and have that person pre-emptively bury the Mueller Report paid off handsomely. The Department of Justice has been comprehensively disarmed and bent to the president's ill will, at great cost to the future rule of law. His various in-broad-daylight acts of corruption, like the Air Force using stopovers and stayovers to prop up Trump's failing Scotland resort or the way the president enriches himself by using his own gaudy Florida resort as the "Southern White House," simply don't add up to something big enough to justify putting the country through impeachment.

The Ukraine scandal changes everything, and as always the president functions here as his own worst enemy. In a way you can think of the president as a kind of political parolee whose only job was to avoid committing new offenses. After seeing his presidency nearly derailed by his campaign's collusion with Russia, and his subsequent efforts to obstruct justice, President Trump had an opportunity, after former Special Counsel Robert Mueller's July testimony, to wipe the slate clean, conduct his administration's business with some baseline level of integrity, and make the election a referendum on the still-strong economy.

Indeed, if the president's advisors could simply kidnap him, hide his phone at a fast-casual salad chain, and then wheel him out for a press conference once a week like some secretly dying autocrat, he might cruise to re-election. But Trump, apparently buoyed by the feeling that he had beaten the Russia rap, immediately got to work on fresh criming, and was stupid enough to do it on a recorded phone call with a foreign leader. Worse, it involved blackmailing Ukraine, an act that plays further into the perception that on some level he is doing Russian President Vladimir Putin's bidding.

Former Vice President Joe Biden, still leading most national polls of the Democratic primary, is likely to be part of the 2020 conversation at least through Super Tuesday in March 2020, even if he ultimately does not secure the nomination. And so the protection racket-style effort to lean on Ukraine to provide damaging information on Biden looks particularly sleazy. It can't be brushed aside as ancient history or blamed on Fusion GPS or what-abouted to death. It has the urgency of now.

Even worse for Trump, he has now backed himself into a corner. If the administration does not release to Congress the full whistleblower complaint from a still-unknown person inside the intelligence community, as well as tapes (not transcripts, which could be doctored) of the call itself, he will be impeached for withholding them. And if the complaint provides credible evidence that Trump abused his powers, either during that phone call with Ukrainian President Volodymer Zelensky or in subsequent conversations, he will be impeached for that. The only thing, at this point, that might spare him impeachment and a Senate trial would be if the accusations turn out to be utterly groundless.

What are the odds of that? In all likelihood, senior Democrats already know what the transcript says and feel certain that the whistleblower's testimony before Congress will be devastating. Reporting already makes it clear that the whistleblower observed a pattern of conduct related to Ukraine so egregious that he or she has taken this enormous risk to bring it to light. It's hard to see the cautious Pelosi and all of these swing-seat Democrats lining up so decisively and publicly behind an impeachment inquiry if they weren't reasonably sure that they have the goods, finally, on Trump.

The president has, thus far, skated by on the craven obeisance of congressional Republicans, all of whom are too collectively terrified of their own primary voters to remove this obviously corrupt goon from office and replace him with Mike Pence. But as my colleague Joel Mathis writes, "This day was inevitable the moment Donald Trump was elected president."

His disregard for the rule of law, his contempt for the Constitution, and his instinctive sleaziness are part of a lifelong record of stiffing contractors, ripping off investors, and convincing others of his grand delusions just long enough to relieve them of their life savings. He brought this dirtball capitalism ethic into the White House with him and didn't change a thing about it. Combined with his towering arrogance and his truly awe-inspiring ignorance, he put himself on a collision course with the Constitution from the moment he sullied the Bible by swearing an oath he had no intention of upholding.

Zelensky, the target of Trump's extortion attempt, was a comedian before he won Ukraine's presidency in April. There's an old saw that says comedy is tragedy plus time. Trump's tragedy might be comedy plus crime.

And his time might be up.

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