>>120906233There thinking is this: they want to keep their power.
Trump's support nationally is deeply divided along party lines: Democrats hate him, Republicans hate him.
If the GOP turns on Trump, then half their supporters could stay home next election.
No matter what Mitch and the GOP half of the Swamp thinks of Trump personally, they have to publicly support him, or risk losing power. As professional politicos they'll do what it takes to hold onto power.