George Will has a superb, and as far as I can tell, spot-on column on what McConnell was thinking when he coupled his vote to acquit with a condemnation of Trump’s conduct:

McConnell knew that if he voted on Saturday to convict Donald Trump, he would have been lionized, briefly, by many of his detractors, who are legion. Because he is the most consequential conservative since Ronald Reagan, his vote would have begun a process to which he is committed, that of making Trump inconsequential. But the time is not quite ripe. Like the author of Ecclesiastes, the Senate minority leader knows that to every thing there is a season…

A McConnell vote to convict Trump on Saturday would have made it easier for the ex-president’s minions to cast the coming 2022 intraparty contests as binary Trump-vs.-McConnell choices. No one’s detestation of Trump matches the breadth and depth of McConnell’s, which includes a professional’s disdain for a dilettante. Trump enthusiasts are as hostile to McConnell as progressives are. He is equally impervious to the disapproval of both factions.