I was watching the rally last Fri night. Before anything happened I was thinking, why have in Chicago, on a Friday night, in the middle of downtown, a minority majority college, give out 25,000 tix when the venue holds less than 11,000? THEN, once the announcement was made that "after consulting with police" they were canceling, all hell broke loose. Then police said they hadn't been consulted. So Trump goes back on tv saying he felt it was in the best interest, etc. and made a great decision. I'm not excusing the protesters. And looking at how young they were, I'm not sure they were "professional". But I have been convinced for the most part, Trump is the "professional". What kind, is not completely clear. JMO.
https://www.washingtonpost.com/blogs/post-partisan/wp/2016/03/13/donald-trumps-chicago-scam/
https://www.washingtonpost.com/blogs/post-partisan/wp/2016/03/13/donald-trumps-chicago-scam/