Damien

There wasn't a gunman. It was a conventional protest and someone else shouted, either mistakenly or with malice intent, that he had a gun and then confusion reigned until the protester was released and it was confirmed there was no gun.

Trump should consider his language because he dehumanises people, angers his base and borders on inciting violence but he shouldn't consider it because of any threat against him. In the latter case the fault lies with the person threatening violence.