Stating the obvious

Unprovoked "preemptive" war has very slim ethical basis under any circumstances. But the question really shouldn't be whether this new Trump war is a good idea. Obviously, I think it is not. But the key point is that it is illegal. There is no Constitutional basis whatsoever for the president to launch a preempitve war, and no conceivable twisting of prior Congressional authorities can be made to apply by any good faith analysis. (This is of course leaving aside the question of violation of International Law, which is also invoked). 

Trump has crossed yet another line, has appropriated unto himself that powers of a dictator and must be impeached and removed from office.