Why didn't Randall Terry "cross-examine" Sen. Casey about abortion? (disrupts event, has little impact instead)

The video at peekURL.com/vyzf9ay shows pro-life activists affiliated with Randall Terry disrupting a speech by senator Bob Casey at an event unrelated to abortion issues. They shouted that he's a hypocrite and that he can't be trusted due to him allegedly supporting funding of abortions in other countries. Needless to say, Casey disagrees, trying to interrupt them and say they aren't telling the truth. In a way this is effective: they got their names in the papers (link, link) and, while Terry doesn't appear to be that mainstream, at least unlike the tea parties types they didn't appear to be drooling idiots with a solipsistic and borderline immoral cause.

On the other hand, they probably didn't change any minds about their cause or about Casey: almost all of his supporters will continue to support him. Spectacles like that on the video might be good therapy for those involved and might be good for fundraising, but it's not the way we should do things in the U.S.

If Terry has issues with what Casey supports, he should find one (1) smart, experienced person to "cross-examine" Casey using real questions at one of his appearances, and during a designated Q&A session. That would prove to be far more effective than just shouting at him. See the question authority page for the details.