An interactive inquiry about why America hasn't been attacked again

That's good news for Iraq but not such good news for Americans who worry about a follow-up to the 9/11 attack. To whatever extent al-Qaida and its affiliates were distracted by the war in Iraq, they aren't distracted now. What happened to all those trained jihadis? Are they redirecting their efforts to plot against the United States? We don't know. The Flypaper Theory earns its place in the worry spectrum not because of what it explains but because of the many imponderables it can't explain.

VI. The He-Kept-Us-Safe Theory

In his Jan. 15 farewell address, President George W. Bush said that after 9/11, "most Americans were able to return to life much as it had been before 9/11. But I never did." He continued:

Every morning, I received a briefing on the threats to our nation. I vowed to do everything in my power to keep us safe. … [T]here can be little debate about the results. America has gone more than seven years without another terrorist attack on our soil. This is a tribute to those who toil night and day to keep us safe—law enforcement officers, intelligence analysts, homeland security and diplomatic personnel, and the men and women of the United States Armed Forces.

A White House fact sheet specifies six terror plots "prevented in the United States" on Bush's watch:

• an attempt to bomb fuel tanks at JFK airport,
• a plot to blow up airliners bound for the East Coast,
• a plan to destroy the tallest skyscraper in Los Angeles,
• a plot by six al-Qaida-inspired individuals to kill soldiers at Fort Dix Army Base in New Jersey,
• a plan to attack a Chicago-area shopping mall using grenades,
• a plot to attack the Sears Tower in Chicago.

The Bush administration deserves at least some credit in each of these instances, but a few qualifications are in order. The most serious terror plot listed was the scheme to blow up airliners headed for the East Coast. That conspiracy, halted in its advanced stages, is why you aren't allowed to carry liquids and gels onto a plane. As noted in "The Melting-Pot Theory," it originated in the United Kingdom, which took the lead in the investigation. (The undercover agent who infiltrated the terror group was British.) We also learned in "The Melting-Pot Theory" that the plan to bring down the Sears Tower was termed by the Federal Bureau of Investigation's deputy director "more aspirational than operational" and that the prosecution ended in a mistrial.

The JFK plot was unrelated to al-Qaida and so technically infeasible that the New York Times, the airport's hometown newspaper, buried the story on Page A37. The attack on the Library Tower in Los Angeles was planned in October 2001 by 9/11's architect, Khalid Sheikh Mohammed, who recruited volunteers from South Asia to fly a commercial jetliner into the building. But Michael Scheuer, a veteran al-Qaida expert who was working at the Central Intelligence Agency in 2002, when the arrests were made, told the Voice of America that he never heard about them, and a U.S. government official told the Los Angeles Times that the plot never approached the operational stage. Moreover, as the story of United Flight 93 demonstrated, the tactic of flying passenger planes into buildings—which depended on passengers not conceiving of that possibility—didn't remain viable even through the morning of 9/11 ("Let's roll").

The Fort Dix plot was inspired by, but not directed by, al-Qaida. The five Muslim conspirators from New Jersey, convicted on conspiracy charges in December, watched jihadi videos. They were then foolish enough not only to make one of their own but to bring the tape to Circuit City for transfer to DVD. A teenage clerk tipped off the FBI, which infiltrated the group, sold them automatic weapons, and busted them. The attempted grenade attack on the CherryVale Mall in suburban Chicago was similarly inspired but not directed by al-Qaida. In this instance, the conspirators numbered only two, one of whom was an FBI informant. The other guy was arrested when an undercover FBI agent accepted his offer to trade two stereo speakers for four grenades and a gun. He is now serving a life sentence.

From a broader policy viewpoint, the Bush administration's most significant accomplishment, terrorism experts tend to agree, was the 2001 defeat of Afghanistan's Taliban regime and the destruction of Bin Laden's training camps. As noted in "The Terrorists-Are-Dumb Theory" and "The Melting Pot Theory," two-thirds of al-Qaida's leadership was captured or killed. Journalist Lawrence Wright estimates that nearly 80 percent of al-Qaida's Afghanistan-based membership was killed in the U.S. invasion, and intelligence estimates suggest al-Qaida's current membership may be as low as 200 or 300.