The fate of President Trump will be decided at a meeting just after he is impeached by the House of Representatives and just before the Senate trial gets underway.

That's when 53 Republican senators will gather to discuss how they will vote. The decision won't be made by individual lawmakers consulting their consciences on the floor of the Senate but in conversation and most likely bitter, acrimonious debate behind closed doors. These leading members of the Republican Party will be deciding not only whether they will vote to remove a president from office for the first time in American history, but also whether they will vote to do so to the president who stands at the head of their own party. That would be a truly momentous deed in the life of the country.

Until now, the possibility of this happening has appeared utterly fanciful. Some members of the Democratic Party's "resistance" to Trump and a handful of center-right Never Trump writers have demanded impeachment from the very start of the administration. But most politicos and pundits have been dubious. As soon as Trump clinched the Republican nomination in the spring of 2016, the party began falling into line behind him. When he shocked nearly everyone by defeating Hillary Clinton, that was the end to any organized opposition. There have been stray critics here and there, but no sign of collective defiance. In that context, the idea that 20 or more Republican senators would vote to eject the Republican president from office has seemed unimaginable.

It may still be. But something has changed. On top of the ever-present, barely concealed disgust for the president that many senators carry around with them nearly every day has been added the appalling spectacle of the commander in chief leaning on the president of Ukraine to produce dirt on his domestic political rival like a two-bit mob boss from Coney Island. That many of those senators treated stories of similarly treasonous behavior as farfetched when they were documented in the Mueller report only made it worse — as has the fact that Trump seems to be so proud of his actions that he's subsequently repeated them, live on camera, with China, explicitly asking its dictatorial government to investigate former Vice President Joe Biden as well.

Many Republican office holders, at least outside of the House, are repulsed. And they're not the only ones. Over the past two weeks, polls have shown a rapid and dramatic swing in favor of impeachment and even conviction and removal from office. As one would predict, support is highest among Democrats, though independents have also warmed to the idea. Republicans remain opposed, but there has been movement there as well. It might not yet be likely, but it no longer seems ridiculous to imagine support for Trump crumbling in the Senate.

Just in the past couple of days, the president has made his situation even more precarious by announcing a badly planned and executed withdrawal of American troops from parts of Syria where they have been protecting the Kurds, working to ensure the defeat of remaining ISIS fighters, and checking Iranian influence in the region. Several senators, including some Trump loyalists, were livid, denouncing the move as a betrayal of our allies and a victory for Iran and Russia. Now, instead of merely worrying that Trump is shredding basic norms of democratic governance, they also need to contemplate the possibility of him seriously harming the country geopolitically.

Assuming impeachment goes forward in the House — and given the White House's latest petulant expression of defiance, it's hard to imagine it stalling out — there will be a vote at which nearly every Democrat and maybe a handful of Republicans will opt to send the matter on to the Senate. That's when a meeting of GOP senators will be organized and convened in a discreet location.

There are 53 Republicans in the Senate. If every Democrat and two independents in the chamber vote to convict and remove Trump from office (a total of 47), achieving that goal (with a two-thirds supermajority vote of 67) will require 20 of those Republicans to turn on the president. (Joe Manchin [D-W.V.] and maybe one or two other conservative Democrats might plausibly vote to acquit Trump, requiring even more than 20 Republicans to join the vote in favor of conviction and removal.) At the meeting, senators will discuss the good of the country, but they will almost certainly be even more preoccupied with the good of the party (which some will say amounts to the same thing).

Removing the president would obviously infuriate Trump's most passionate supporters. The best way for the party to insulate itself electorally from that fury would be for those senators facing re-election in 2020 — there are 23 of them — to be let off the hook and encouraged to vote for acquittal if that's what will help them win their states.

That will leave 30 senators whose seats are safe until 2022 or 2024. If the party decides to turn on the president, 20 or so out of those 30 will be the ones to enact it. The bulk of the meeting will involve those 30 people hashing out what they will do, and precisely who will do it. The meeting won't come to an end until a resolution has been reached about whether or not to dump Trump and bet that President Mike Pence (perhaps with running mate Nikki Haley by his side) will have a greater chance than Trump of defeating Biden or Sen. Elizabeth Warren (D-Mass.) in November 2020. The hope will be that by 2022 and beyond, all will be forgotten and forgiven by the Republican base.

When voting begins at the conclusion of the Senate trial, the outcome will already be known to the Republicans in the room. Either no Republicans will turn on Trump — or a fatal number will. There will be no surprises, no wasted votes for conviction and removal, no senators taking a noble stand uncertain of the final tally. (The only one who might possibly vote to convict and remove knowing its futility is Sen. Mitt Romney, a morally scrupulous Mormon who is very popular in his home state of Utah — and isn't up for re-election until 2024.)

We can't yet know the outcome of such a meeting. But we can know that there will be such a meeting. And that Trump's fate will hang in the balance.

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