Trump is slitting his own throat by not unifying the country after the bombings

If you understand his incurable mental condition which is a personality disorder called: "Narcissistic personality disorder" (which Hitler also had by the way) then you understand why he cannot unify the country.

It goes in his mind something like this: "I can do no wrong. So I never have to apologize for anything I say or do because I'm perfect."

This is a part of his mental condition that prevents him from apologizing for causing the pipe bomber to do this in the first place. But, around people without a personality disorder caused usually by an extreme trauma (in his case the death in his 40s of his Brother Freddie from alcoholism) he cannot perceive that he is at fault because of this mental disorder. But, among normal people who are psychologically healthy he is slitting his own throat right before the elections.