What Difference Did 9/11 Make?

The terrorist attacks of September 11, 2001, were a horrific shock. Images of trapped victims leaping from the Twin Towers are indelible, and the intrusive security measures introduced in the wake of the attacks have long since become a fact of life.

But skeptics doubt that it marked a turning point in history. They note that the immediate physical damage was far from fatal to American power. It is estimated that the United States' GDP growth dropped by three percentage points in 2001, and insurance claims for damages eventually totaled over $40 billion — a small fraction of what was then a $10 trillion economy. And the nearly 3,000 people killed in New York, Pennsylvania, and Washington, DC, when the al-Qaeda hijackers turned four aircraft into cruise missiles was a small fraction of US travel fatalities that year.

While accepting these facts, my guess is that future historians will regard 9/11 as a date as important as the Japanese attack on Pearl Harbor on December 7, 1941. The surprise attack on the US naval base in Hawaii killed some 2,400 American military personnel and destroyed or damaged 19 naval craft, including eight battleships. In both cases, however, the main effect was on public psychology.

For years, President Franklin D. Roosevelt had tried to alert Americans to the Axis threat but had failed to overcome isolationism. All that changed with Pearl Harbor. In the 2000 presidential election, George W. Bush advocated a humble foreign policy and warned against the temptations of nation-building. After the shock of 9/11, he declared a "global war on terror" and invaded both Afghanistan and Iraq. Given the proclivities of top members of his administration, some say a clash with Iraq's then-dictator, Saddam Hussein, was predictable in any case, but not its manner or cost....