Juan Zarate, the top counterterrorism official in President Bush’s White House, says, “The administration smells blood here. I think al-Qaida is on its heels.”

Zarate, now with the Center for Strategic and International Studies, points to three things that show the space where bin Laden can move freely is shrinking.

First is the Pakistan army’s offensive against the Taliban in Swat Valley and other areas…

The second element shrinking bin Laden’s possible location is the 21,000 additional U.S. troops pouring into Afghanistan. And Zarate points to a third factor: drones.