No, he hasn't.
He has encouraged his supporters to fight back, and not to give in to these orchestrated disruptions by the Left and with approval from the GOP establishment.
People see what's going on in Baltimore and U of MO and they're not going to cave in to these leftist radicals.
Do you think these agitators will behave if Cruz somehow wins the nomination?
Trump has left himself vulnerable through his loose talk and advocacy of violence from the podium and in front of the TV cameras.
At some point Trump’s get-out-of-jail-free card must be turned back in. He can’t be saying that sort of thing, because people who really are violent, like these thugs, will sieze on any excuse.