Setup or not, the Congressman was an idiot. If we was going to engage the student, he should have done so respectfully, even moreso given the presence of the camera, regardless of the legitimacy (or lack thereof) of the question or the questioner. If he was incapable of doing so, he should have just continued walking, perhaps making a dismissive comment such as, "This is not the time or place for this kind of question." I agree with bodyman on this one--there is absolutely no justification for this kind of physical response to a (n admittedly loaded) question posed by a nobody, especially from a public figure who has a responsibility to maintain a positive public image.