2B: How important is it that we track down Bin Laden? Why haven't we been able to do so?
Cochran: We should certainly kill him. It sets an important precedent. As to why we haven't, I think finding someone in the Northwest Provinces of Pakistan is probably hard, and we're worried about upsetting the applecart there -- and I think we didn't want to, not much. Look at the resources committed. Judge them by their fruits.
The whole thing is worth a read. Look here.