I am a Liberal, and think the riots that took place at the Berkeley campus were totally wrong headed. These misguided rioters violated the very principles that claim to cherish. I very much disagree with the Breitbart mentality, however to deny this person the right to speak will not help the Liberals or their political movement. Liberals claim to cherish free thinking and freedom of expression, it's time they start practicing what they preach. This was just plain dumb!
According to press reports, the University took every reasonable measure to ensure that Yiannopoulos could speak, they provided campus security personnel and an area for protestors to protest peacefully and apparently all was going smoothly until 150 or so outside agitators dressed in all black showed up and triggered the "riot".
So it would be unfair to to blame this one on the University or the student body in general, the University did as much as it could to protect freedom of expression and the bulk of the student body (including those that were protesting peacefully in the designated area) weren't the ones perpetrating this craziness. I think it would behoove "liberals" to find out exactly where these black garbed agitators came from and roundly condemn whatever organization/cause they represent; since they and those like them are the ones that are making you folks look bad.