 Horrible thing, amazing thing, and in many ways it changes your attitude, your viewpoint on life. Trump has said the experience had him tearing up and rewriting the speech he'll deliver this evening. Jim Ryan, ABC News, Milwaukee. There have been growing calls for the head of the Secret Service to step down amid new information about the attempted assassination. Law enforcement officials confirmed that 20 minutes had passed between when the Secret Service snipers first noticed the shooter and when the shots were first fired.