NSA Spying On America: Stopping Terrorist Plots? Or Not?

Recently on Air America radio, I heard an audio clip of CNN's "Situation Room's" Wolf Blitzer interviewing republican Senator Bill Frist about the NSA spying on Americans. Wolf asked if in the five years since it began, has the NSA spying prevented any terrorist plots?

Naturally, Sen. Frist didn't answer. Wolf pressed the point, asking if even one terrorist plot had been prevented. Frist didn't even answer that one. Which proves Frist is a pathetic repubican loser, who knows the NSA spying on Americans has no value, beyond spying on w.'s political enemies (you know, Quakers & such).