In the wake of 9/11, the United States was quick to target Afghanistan as the home base for global jihad, invading the south-central Asian nation almost before the dust from the twin towers had settled.
But terrorism experts say the capture of Faisal Shahzad, the Pakistan-born man who allegedly tried to detonate a car bomb in Times Square last week, points to a new reality: In the years since the 9/11 attacks, the landscape has shifted -- and Pakistan is now ground zero for Islamic terrorism.
The country's lawless tribal regions have become widely known as hotbeds of radical Islamic sentiment and centers for terrorist training, says Steven Emerson, executive director of the Investigative Project on Terrorism.
"That's where a lot of terrorists are openly operating -- that's why this guy went back and forth a number of times," Emerson says. "You've got probably two dozen Islamist terrorist groups operating there. If you don't hook up with al-Qaida you can hook up with Jaish-e-Mohammed. If you don't hook up with Jaish-e-Mohammed, you can hook up with Lashkar-e-Taiba."
Indeed, several recent terrorism cases involving U.S. residents seem to bear out Emerson's view.
In March, five young men from northern Virginia were arrested in Pakistan after they allegedly sought to join al-Qaida there. Pakistani officials charge that the men, who range in age from late teens to mid-20s, had planned to fight U.S. soldiers in Afghanistan and possibly attack targets in the United States.
That same month, David C. Headley, a Pakistani-American businessman, pleaded guilty to federal terrorism charges stemming from his involvement in the 2008 Mumbai terrorist attacks, in which 163 people were killed. Headley, who has ties to upper-level members of Pakistan's government and military, acknowledged receiving training in Pakistani terrorist camps.
In February, Najibullah Zazi, a legal resident of the United States, pleaded guilty to charges he had planned suicide attacks in New York City's subway system. An Afghan citizen, Zazi underwent weapons and explosives training at an al-Qaida training camp in Pakistan.
Furthermore, experts say that the majority of those involved in U.K. terrorist attacks are of Pakistani extraction or have some connection to the Islamic republic.
"The Pakistani community seems to produce a disproportionate number of jihadists, both in Pakistan and in the Pakistani diaspora," says RAND Corp. terrorism expert Angel Rabasa, author of "The Muslim World After 9/11." "I believe that this is because of the linkages to well-established, deeply rooted terror networks in Pakistan."
Where terrorists succeed, Rabasa notes, they inevitably are linked to organizations that convey motive, training and technical skills.
Rabasa stresses that Pakistanis are not predisposed to terrorism and that the vast majority have nothing to do with terrorists. Still, he says, "given that Pakistan is the epicenter of global Islamist terrorism, it tends to capture and recruit individuals with Pakistani backgrounds."
If the United States hopes to thwart Pakistan-bred terror, he adds, it will require a much-improved intelligence-gathering operation.
"Because of these linkages, terrorism cannot be dealt with with police measures alone or preventive measures," he says. "What's needed is much better intelligence about who is in contact with networks in these places and what are the nature of these linkages."
Such intelligence, though, can be hard to come by. Part of the problem, Emerson says, is that Pakistan has not cooperated sufficiently with U.S. efforts to curb terrorism.
"Pakistan is a failed nation state, it's the Old West," he says. And although it has improved its cooperation with America, its efforts leave much to be desired.
"We have drones, but drones take out two to three leaders a week, or whatever," he says. "You're not going to win the war that way. This requires Pakistani cooperation that hasn't happened yet -- the pressure needs to be brought to bear on Pakistan intensively."
Pakistan, for its part, insists it is doing all it can -- and places the blame for jihadi activity in the region squarely on its neighbor Afghanistan.
"Do you know how many terrorist attacks have been carried out within Pakistani cities?" says Jaffar Hussain, Pakistan's consular attache in Los Angeles. "Each and every city is targeted by these bloody people. How could we favor them? We are killing them. They are running toward the borders. They are coming from Afghanistan. They are trained in Afghanistan.
"They are not jihadis," Hussain says. "They are butchers."