John Derbyshire's Question

National Review Online’s John Derbyshire asks the following question about the relationship between democracy and terrorism:

Given that the four London suicide bombers were all raised -- in at least one case, born and raised -- in Britain, the quintessential liberal democracy; and given that the entire premise of current U.S. policy is that we can end suicide bombing and other terrorism by bringing liberal democracy to the Middle East; shouldn't we be re-thinking our policy?

In theory, the Westphalian nation-state system exists to control the use of violence by limiting its legitimate use to the appropriate sovereign authority. But the Westphalian system failed to stop the September 11 attacks on the United States by foreign nationals. As a result, should we not be re-thinking the usefulness of conducting foreign policy according to Westphalian rules?