Homecoming

In the eight years after September 11, and especially during the Bush administration's first term, Americans became all to accustomed to a diet of orange alerts, sensational terror arrests, and breathless press conferences announcing the thwarting of yet another serious plot. But months and years down the line, it often emerged that such plots may not have represented such grave threats after all: terrorism suspects were charged with less serious offenses or released altogether; plotters turned out to have little or no capacity to launch attacks; and, often, when juries did convict, it emerged that entire conspiracies were reliant on the helping hand of undercover law-enforcement agents.

But 10 days ago federal agents in Denver foiled an alleged plot on U.S. soil  that, for the first time, appears to have posed a true and severe threat to the U.S. homeland. Najibullah Zazi, a permanent resident of Afghan nationality, pled not guilty Tuesday in his arraignment in Brooklyn to charges including conspiracy to use a weapon of mass destruction. He is believed to have trained to make bombs with Al Qaeda in the Federally Administered Tribal Areas (FATA) of Pakistan and to have initiated plans—apparently without assistance from undercover agents—with others in the United States to perpetrate a terrorist attack in New York City. The FBI, in other words, has just thwarted the most serious plot, by far, on U.S. soil in the last eight years.

And this is just the beginning. The threat from Al Qaeda to the U.S. homeland is arguably more acute now than at any time since September 11. This is not because Al Qaeda has become a stronger foe. (On the contrary, Osama bin Laden's terrorist network has actually been weakened in the last two years by intensified U.S. missile strikes against its leadership in FATA and a sharp backlash among Muslims worldwide against its violent excesses.) It is because a growing number of Americans have gone to FATA, the global hub of Al Qaeda's terrorist operations, to join the jihad in Afghanistan—something which was very rare until recently—and Al Qaeda, opportunistically, has recruited them for attacks on their country.

The number of American residents who had joined or trained with Al Qaeda between its founding in 1988 and the September 11 terrorist attacks numbered only in the single figures. They included Wadih El-Hage (bin Laden's private secretary), Ali Mohammed (an American Special Forces instructor of Egyptian origin), Christopher Paul (a man from Columbus, Ohio, who joined Al Qaeda in Afghanistan in the early 1990s), Iyman Faris (another Columbus man of Kashmiri descent who trained in a Qaeda facility and, rather fancifully, planned to destroy the Brooklyn Bridge with gas cutters and a blowtorch in 2003), Adam Gadahn (a Californian Christian convert to Islam who has become one of Al Qaeda's spokespeople), and John Walker Lindh (the so-called American Taliban).

After September 11, even fewer American residents allegedly linked up with the terrorist group. They include Aafia Siddiqui, a female MIT graduate who will go on trial later this year in New York; her associate Majid Khan, a former Baltimore resident currently being held in Guantánamo Bay; and Mohammed Junaid Babar. His example is the most disturbing. A Pashtun trainee taxi driver from Queens, N.Y., Babar met with several Qaeda commanders in the Afghan-Pakistan border region between 2003 and 2004 and organized bomb-making lessons for himself and a band of British jihadists—including two of the 2005 London suicide bombers. He was arrested after his return to New York in 2004 and pleaded guilty to assisting Al Qaeda. Then, as a star witness in subsequent terrorism trials, he testified that he once contemplated how an attack could be launched on New York's Times Square.

Still, those examples were exceptions to the rule. Twenty years after Al Qaeda was founded, an average of about one American resident had joined its ranks every two years. Suddenly, though, in the spring of 2008, this slow trickle became a flood. In the past 18 months, at least a half dozen recruits may have trained with Al Qaeda in the FATA. The new trend got started that March, when a young American from Long Island, N.Y., scribbled his signature on a Qaeda recruitment form provided to him by his handlers in the FATA, becoming the first American citizen to formally join Al Qaeda's fighting ranks since the 9/11 attacks.