Oh, fuck off, Travis, and especially Dr. Carson, who was a spectacular neurosurgeon and is otherwise a weapons grade moron. A man so stupid he doesn't understand the Constitution he proclaims to love.
This isn't about freedom of speech. There's no freedom of speech problem here. Trump was holding a private, ticketed event. He rented the hall for a private event. That literally precludes the concept of freedom of speech, which is regarding government interference in speech. What happened is people bought tickets to the Trump event and were removed, and the crowd got testy at them, primarily because Mr. Trump has been encouraging them to do so.
Trump cancelled his rally not because it wasn't safe, but because it was a political move to do so, to win a political cycle. And it worked. It was brilliant and genius and it reinforces his narrative among his targeted audience, way more so than actually appearing would have done. It is, in fact, one of the things Trump has done that shows political savvy and intelligence, and we should talk about it significantly for that.
But freedom of speech? Fucking learn what it means before you complain it was taken away.