Remember, they never liked him in the first place.
Plan B is far more appealing. Becoming the party of impeachment at a time when impeachment is popular transforms crisis into opportunity, allowing Republicans to cleanse their Trump-era sins (trying to repeal the increasingly well-received Obamacare, paying for the Great Wall of Mexico with deficit spending, etc.) and seize the moral high ground in one swoop. Vice President Mike Pence takes the helm, steadies the ship, promotes their right-wing agenda with more grace than his former boss, and Ryan and his buddies prepare for 2020.
As for the Democrats, this scenario leaves the party even more damaged than it is today. If they leave the task of deposing a wounded Donald Trump to the Republicans, they'll likely never recover.
Still seething over the DNC's shabby treatment of Bernie Sanders, the progressive base would consider the party completely discredited and hopelessly moderate for failing to lead the charge against Trump. Swing voters, and not a few Democrats, will give Team Ryan credit for their integrity in taking down one of their own. I can imagine the Warren wing forming a new Progressive Party, leaving the Democrats at less than half its current level of support.
Dems could dodge this looming catastrophe by declaring all-out war against the president. For example, Democratic lawmakers could shut down Congress, and thus deny Trump his entire agenda, by denying a quorum -- i.e., failing to show up until the president agrees to resign. There are many ways to obstruct. But creating a constitutional crisis would require balls -- something in short supply among Congressional Democrats.
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