It's nowhere near the worst or most consequential thing he's done, but I think Trump's threat to demolish the Kennedy Center if he isn't allowed to name it after himself is the clearest demonstration yet that he's gone mad with the imagined power of his office.
It doesn't advance any policy goal, and no constituency has been calling for it. He doesn't even particularly benefit from it. It's just a pure, simple expression of a corrupt ego out of control.
@mattblaze He hasn't "gone" anything. Look, I live on the opposite side of the planet & even I have known since before his first term that this dude can be fully encapsulated by "dumber than a flaming barrel of monkey poop" + "100% pettily malicious". He has always wanted to destroy anything & anyone who doesn't please him - the only difference now is he's found out that people will let him do it.