A year after the U.S. raid that killed Osama bin Laden, al-Qaida is hobbled and hunted, too busy surviving for the moment to carry out another Sept. 11-style attack on U.S. soil.
But the terrorist network still dreams of payback, and U.S. counterterrorist officials warn that, in time, its offshoots may deliver.
A decade of wars in Iraq and Afghanistan that has cost the U.S. about $1.28 trillion and the lives of 6,300 U.S. troops has forced al-Qaida's affiliates to regroup, from Yemen to Iraq. Bin Laden's No. 2, Ayman al-Zawahri, is thought to be hiding, out of U.S. reach, in Pakistan's mountains, just as bin Laden was for so many years.
"It's wishful thinking to say al-Qaida is on the brink of defeat," says Seth Jones, a Rand analyst and adviser to U.S. special operations forces. "They have increased global presence, the number of attacks by affiliates has risen, and in some places, like Yemen, they've expanded control of territory."
White House counterterrorism adviser John Brennan says there's no sign of an active revenge plot against U.S. targets, but U.S. citizens in Pakistan and beyond are being warned to be vigilant ahead of the May 2 anniversary of the night raid. U.S. helicopters swooped down on bin Laden's compound in the Pakistani army town of Abbottabad, killing him, one of his sons, two couriers and their wives.
U.S. counterterrorist forces have killed roughly half of al-Qaida's top 20 leaders since the raid. That includes U.S.-born cleric Anwar al-Awlaki, killed by a drone in Yemen last September, less than six months after bin Laden's death.
Yet al-Zawahri is still out there. Though constantly hunted, he has managed to release 13 audio and video messages to followers since bin Laden's death. He has urged followers to seize on the unrest left by the Arab Spring to build organizations and influence in Egypt, Libya and elsewhere, and back rebels in Syria.
Al-Qaida also takes shelter in Pakistan's urban areas, as shown by the bin Laden raid, and the CIA's efforts to search those areas is often blocked by the Pakistani intelligence service. U.S. officials say they believe factions within the agency shelter and even fund al-Qaida's senior leaders. Pakistan denies the charge.
Afghanistan is the temporary home to up to 100 al-Qaida fighters at any single time, U.S. officials say, adding that a steady series of U.S. special operations raids is essential to keeping them out. With the withdrawal of U.S. forces, U.S. counterterrorism officials fear al-Qaida could return.
The terror group's presence is still greatest in Iraq, where intelligence officials estimate that up to 1,000 fighters have refocused their campaign from striking now-absent U.S. troops to hitting the country's Shiite-dominated government.
Yemen's al-Qaida of the Arabian Peninsula is becoming a major draw for foreign fighters as it carves out a stronghold in the south of the country, easily defeating Yemeni forces preoccupied battling tribal and political unrest. In 2009, one of the group's followers tried to bring down a jetliner over Detroit.
Al-Qaida affiliates such as al-Shabab in Somalia are struggling to carry out attacks in the face of a stepped-up CIA/U.S. military campaign and a loss of popular support after blocking U.N. food aid to some 4 million starving Somalis, officials say.
But the group is kept afloat by a stream of cash, partly from piracy and kidnapping off the Somali coast. According to Brennan, total ransom payments to Somali pirates increased from approximately $80 million in 2010 to $140 million in 2011.
Cutting off those finances by persuading companies to stop paying up is now central to the terrorism-fighting effort.
So, too, is the strategy of fighting small, smartly and covertly, avoiding land invasions such as those in Iraq and Afghanistan that caused Muslim outrage and helped draw fresh recruits, says Rand's Jones.
Many U.S. officials cite the Yemen model as the way ahead: a small network of U.S. intelligence and military forces working with local forces to selectively target militants.
"The key challenge," says Robert Cardillo, a senior official in the Office of the Director of National Intelligence, "will be balancing aggressive counterterrorism operations with the risk of exacerbating [al-Qaida and its allies'] anti-Western global agenda."