The War That Must Never Be Fought borrows its title from President Ronald Reagan's State of the Union message of 1984 in which he declared "a nuclear war cannot be won and must never be fought.” In this introduction, former Secretary of State George Shultz relates how he felt on learning that U.S. atomic bombs had destroyed two major Japanese cities and paved the way for the end of World War ll in the Pacific.

The scarcity of significant terrorist attacks in recent years has led Americans to assume that the days of mass casualty attacks are in the past. But history teaches us to beware of the assumption that recent trends foretell the future. Americans are paying insufficient attention to unexpected events in which terrorists inflict serious harm on the United States.

Although we have become much more capable at detecting terror threats to the homeland, our enemies are determined and ingenious. The most-frequent threats we will face are lone-wolf or small-group terrorists inspired by notions of jihad but acting in relative autonomy; however, Islamist fanatics will not stop attempting to stage dramatic large-scale strikes against the United States.

Americans must be realistic about what they expect from allies. We rightly prefer to engage on a multilateral basis and with as broad a coalition as possible. But too often we find ourselves surprised, offended, and alienated when our partners, especially regional states, seem to pursue their own interests at the expense of what we see as the common good.