I think this is it:
Fact no. 1:Assume Jeff Flake has a morbid, obsessive hatred of Trump.
Fact no.2: When you are confused or wondering about anything motivating Flake, go back to Fact no.1.
What is Flake’s end game?
Run as Dem at point in future?
Dem Lobbyist?
Academic? President of BYU?
Your choices for Flake...