She's invited to speak and over a thousand people come to hear her. A dozen or so hecklers attempt to drown her out. If the security personnel aren't going to do anything about it, the speaker has to. If they - the hecklers - want to debate her, wait in line for the Q&A session.
Generally, I've got no problem with that. I don't like hecklers. But I equally don't like speakers who bait people intentionally in an effort to generate heckling, which is what I think she was doing.