I hate to break this to you (reality), but....
he already has done something to hurt America or Americans. He supported and donated to the very same leftist Democrats that have been feverishly working to destroy us from within. The only question is, was it, in fact, "purposely"? If so, Trump is a danger to the USA as CIC. And even if not, if he's that clueless, uninformed and bumbling....we can ill afford yet another president 'like that' at this crucial time. And yeah, that is a harsh reality that we are facing. You might want to try to get used to facing it. It ain't going away.
Why don't you wait until Cruz drops out, (I predict within 30 days) then come back when you have something to really complain about.