Not “weak-kneed”; treasonous.
Problem: the RINOs like Mitt never had character and a belief in America if it ever conflicted with their personal careers and wealthbuilding to start with, so expecting them to suddenly be ready for a starring role in a chapter of a new edition of Profiles in Courage is unrealistic.
As Harry Truman said of the politicians: If you want a friend in Washington, get a dog.
Everyone in DC listens all day long to the radio station WII FM (call letters stand for What’s In It For Me).