Here it is, the first YouTube to dent Rudy Giuliani's image since the old "government-funded abortions for all!" speech.
Marc Ambinder has the best take on this.
One cannot listen to this excerpt of Giuliani, taken from an apperance before the Kennedy School of Government in 1996, and conclude that, in the back of his mind, Giuliani was somehow arguing that if only our law enforcement techniques got better, we'd be able to solve the problem. He was making an affirmative argument that solving the problem itself could be more harmful than preserving the status quo So—clearly—Giuliani's argument has changed.
Reporters have been pointing out for a while that Giuliani's fundamental thinking on immigration didn't match up with what he was saying to angry crowds, but the response was a collective "eh" sometimes accompanied with a "whatever." Driving the point home absolutely requires this kind of visual proof. Seeing the man contradict himself has a power that you can't get in prose, and it's harder to challenge the provenance of a video camera than to challenge a reporter's anecdotes and facts and bias, as some conservatives did with Wayne Barrett's latest Rudy expose.