Trump cancelled his rally in Chicago last eve claiming the Chicago police advised it. The police denied that happened. From USAToday.com
Anthony Guglielmi, a police department spokesman, said the Trump campaign did not consult the police department before canceling.

"They did not consult us at all," he said. "The decision was made by the campaign on its own."
Nonetheless, he has been inciting the violence which is escalating at his events. When you tell your supporters that those who disagree with you are destroying the country and that in the good old days we would just beat them up. The protesters are the enemy and if you get arrested for attacking them I Mr Trump will take care of your defense. How can you not be held responsible for the exact behavior you encourage?

This direct connection between Trump's speeches and the behavior of his supporters is not just being made by the left, his remaining GOP opponents have made exactly the same charge. To see the increasingly angry pro-violence speeches Trump is making,
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I will below transcribe some of the speeches.