Virtually everyone who has called for Churchill's removal makes the same argument: "What if it was your son/husband/mother killed in the towers?" But that is not an argument for suppressing speech—particularly on college campuses and particularly at a forum ostensibly testing the "limits of dissent." It's an argument for making all political discourse conform to the sensibilities of the most fragile victim. It's an argument for banning any discussions of the American Revolution in history classes because some student may have burnt her tongue on a mug of tea once.
In his essay On Liberty, John Stuart Mill wrote:
[T]he peculiar evil of silencing the expression of an opinion is, that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of the opportunity of exchanging error for truth: if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth, produced by its collision with error.
We can none of us learn anything—not our college kids and not our choleric talk show hosts—if our fixed notions aren't challenged. In a perfect world they would be challenged by scholars and intellectuals rather than cheap provocateurs. But it's ultimately the university's task, not mine or yours, to draw that distinction.