I would go so far as to say that this has always ben the plan, at least this time around. I find it highly suspicious that Trump has been the target of assassination attempts by republicans twice (plus a foreign attempt on his life) already. We're being prepared to accept this as expected when it finally happens, and it has to happen in order to give Vance the pretext to implement martial law and usher in the high-tech Handmaid's Tale scenario his patrons want. Trump is their useful idiot; but useful only because he is populist and charismatic enough to get them in power via ordinary electoral process. Once they suspend that process entirely they no longer need him and in fact he becomes a liability; offing him kills two birds with one stone.