Free speech, which has had its ups and downs on the UNC-Chapel Hill campus over the years, suffered an embarrassing setback Tuesday night. A crowd's vocal protests, pepper spray from the campus police and a window broken by a fist-pounding protester disrupted an appearance by Tom Tancredo, the former Colorado congressman.

Tancredo was forced to leave without completing his speech at Bingham Hall. The university is left to pick up the pieces, if it can, of its reputation as a place where free speech is welcomed. ...

When protesters hound a speaker off a campus stage, that campus forfeits some of its standing as a beacon of tolerance and inquiry. When a well-known figure on one side of a public policy question is silenced, legitimate debate is the loser. (At UNC, the focus was on in-state tuition for illegal immigrants who are North Carolina high school graduates, an issue on which this editorial page takes the opposite view from Tancredo.) And when a professional firebrand goads people into disruptive acts, he wins – and they end up with egg on their faces.