Trump doing absolutely nothing but standing around menacingly will actively kill the left. They need the impeachment, they need to go out for blood. Each and every day, they look more and more crazy. They have to destroy the guy, can't let him have any accomplishments that get marked by history, can't let anyone inspired by him, ever gain political power. MUST DESTROY.
And at the same time, they are going to let everything else around them go to shit.
Liberals need Trump as a kind of reflecting pool. Without them knowing where exactly he stands on issue X, they are then forced to actually to do some thinking, instead of blindly opposing him which is much easier. They need to see everything in black and white, heroes and villains. Ambiguity makes them exceedingly anxious.
they have no one to accuse of exactly what they are doing at the moment