I think it's a unique form of political question, on account of the mechanism used to seat and remove political figures.
A parallel is the power of Congress to unseat its own members - once unseated, they can call the cops to enforce a trespass action. But unseating is a prerequisite.
So with the president, Congress seats the person, Congress is supposed to insure the person is qualified, and there is a big gaping hole as to how to react when Congress is derelict.
there is a big gaping hole as to how to react when Congress is derelict.
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I doubt that our Founding Fathers ever imagined that the entire congress would be a united treasonous front.