I feel that while we are indeed engaged in a war against terror, it is inadequate and even misleading. If Churchill had informed the country in 1940, we are engaged in a war against bomber aircraft and submarines, that would have been an accurate statement but not a very helpful one. To say we are engaged in a war against terror is of the same order. Terror is a tactic. It's a method of waging war. It is not a cause, it is not an adversary, it is not anything that one can identify as an opponent, and I think we need to be more specific in fighting a war. It's useful to know who the enemy is. I think you would agree.

Islam and the West: A Conversation with Bernard Lewis (2006)