Another thing which has troubled him, Levin said is the constantly criticism of the US for its drone attacks inside Pakistan.

"I guess yesterday, the day before, we got a number of very high-level targets. There is civilian casualties, which obviously are to be minimized and regretted. But when we knock out high-level targets, terrorist targets, Taliban targets that are out to destroy the government of Pakistan, the least we can expect, I believe, from the Pakistan government is silence," Levin said.

"What I can't understand and do not accept is the attacks on us, the criticism on us, because what that does is undermine the effort. Every time they attack us as being foreigners attacking their sovereign soil, they are creating another generation that are after us instead of after the terrorists," Levin argued.