"Obama certainly stepped up the use of drones, and it's fair to say it's had a strong effect," says Ed Turzanski, professor of political science at La Salle University. "It plays to our strength and their weakness. The Air Force is asking for more, and the CIA is fitting drones with sophisticated recognition technology. It's the future."
The war on terror has been a learn-as-you-go process, says Matthew Levitt, director of the counterterrorism and intelligence program at the Washington Institute for Near East Policy. He likes the way technology and interrogation built on each other. "Every time you interrogate someone," Levitt says, "you collect information, and you can use that in your next interrogation. Our capabilities kept improving as we got more experience."
Interrogation of three top terrorists - Khalid Sheikh Mohammed, Hassan Ghul, and Faraj al-Libi - helped identify Sheikh Abu Ahmed, a courier for bin Laden. In mid-2010, a cellphone call from Ahmed to a person under U.S. surveillance helped the National Security Agency identify him.
Like bin Laden, Ahmed was tech-smart, disabling his phone and taking out the battery before going anywhere near bin Laden's hideout in Abbottabad, Pakistan. But sometime in mid-2010, Ahmed slipped, made a single incautious call, and bin Laden's cover was blown.
"There the credit has to go to the guys at NSA," says Lawrence Husick, senior fellow at the terrorism center of the Foreign Policy Research Institute. "They cast these huge nets into the ether, filtering phone calls, doing vocabulary matching and voice matching, sifting fragments of conversation for clues. And they got a big one."
For the next eight months, relying on government and commercial satellite systems, and on surveillance drones, U.S. experts kept a 24/7 vigil over bin Laden's compound. Comparing present and past photos, they learned the site was built in 2001 and the three-story mansion added in 2005. They learned the place so well that a full-scale replica was built at Bagram Air Base in Afghanistan, so U.S. forces could practice storming it.
The clue was what was not there, says Husick: "Bin Laden and his associates in al-Qaeda have . . . used the Internet for coordination, communication, indoctrination, and training, and yet this facility had no phone, no Internet, no satellite dish, just a power line running to it.
"He was almost certainly aware that any use of communications would allow us to track him," Husick says. "So, to stay off the radar he had to sever these ties. What our guys had to look for was an absence of the normal kinds of connections and signals."
The May 1 assault employed helicopters, night-vision cameras in the helmets of Navy SEALs, precision firearms, and real-time communications. Sitting at CIA headquarters, Director Leon Panetta gave Obama and his team instant updates. Panetta announced, "Geronimo EKIA," and they knew the enemy had been killed in action.
A Navy SEAL took a photo of bin Laden's body and uploaded the image to experts who used facial-recognition software to make a 95 percent certain identification. That was instantly sent to Panetta, who relayed it to the White House. Later, DNA analysis compared material collected from the body with that from (so far unspecified) bin Laden relatives, increasing certainty to 99.9 percent.
With the discovery of a cache of computers and flash drives at the bin Laden compound, the CIA is now at work in the young science of cyberforensics - the study of evidence in virtual or computer resources.
Most impressive of all? The secrecy, says Turzanski: "Only those we wanted to know about the mission knew about it," he marvels, "and that's a real departure."
Contact staff writer John Timpane at 215-854-4406, jt@phillynews.com, or at Twitter at @jtimpane.