Until recently, the United States had become complacent about terrorism. The general view was that al Qaeda was on the run and Islamic terrorism was a receding threat. We now know better.

A string of attacks by Islamic terrorists—an officer murdering his fellow soldiers at a U.S. army base, a passenger's attempted bombing on a Detroit-bound airplane, and a double agent's suicide bombing a CIA base in Afghanistan—reveals the continuing and growing danger of Islamic terrorism. Hostility to the U.S. appears to be increasing...