The best answer in last night's Democratic presidential debate came not from the leading contenders but from Senator Joe Biden.
In his usual manner, moderator Tim Russert tried to put the candidates into a corner with one of his yes-or-no questions that do not allow for nuance or complexity:
MR. RUSSERT: Senator Biden, would you pledge to the American people that Iran would not build a nuclear bomb on your watch?
Hillary Clinton, Barack Obama, and John Edwards each wiggled his or her way out of the question, essentially pledging to do what they could to prevent Iran from developing nuclear weapons. Then Russert turned to Biden, and Biden threw the question back in Russert's face.
SEN. BIDEN: I would pledge to keep us safe. If you told me, Tim -- and this is not -- this is complicated stuff. We talk about this in isolation. The fact of the matter is the Iranians may get 2.6 kilograms of highly enriched uranium; the Pakistanis have hundreds, thousands of kilograms of highly enriched uranium.
If by attacking Iran to stop them from getting 2.6 kilograms of highly enriched uranium, the government in Pakistan falls, who has missiles already deployed, with nuclear weapons on them, that can already reach Israel, already reach India, then that's a bad bargain.
Presidents make wise decisions informed not by a vacuum in which they operate, by the situation they find themselves in the world. I will do all in my power to stop Iran from getting nuclear weapons, but I will never take my eye off the ball.
What is the greatest threat to the United States of America: 2.6 kilograms of highly enriched uranium in Tehran or an out of control Pakistan? It's not close.
Biden was taking the mature approach to foreign policy, daring to challenge the false dichotomy: let Iran go nuclear or start a war. A nuclear-armed Iran would indeed be a problem, but a U.S. military strike against Iran could cause greater problems. National security is not always an either/or proposition. Yet Russert, with his gotcha query, was trying to force the complicated Iran issue into such a box. This sort of framing does pervert the national debate, for it precludes serious discussion of the matter at hand and careful consideration of consequences. It also suggests that Americans can have it all—that is, a nuclear-free Iran without creating other difficulties.