Bush authorized a change in the rules so that Predators could fire missiles when there was a much lower confidence—50 to 60 percent—that non-Pakistani "foreign fighters" were present at a targeted location. Under the new rules, the U.S. launched an estimated 30 Predator-based missile attacks since last summer on targets inside Pakistan.

But according to an account in Wednesday’s New York Times, Pakistani intelligence officials told the paper that Al Qaeda has responded to the attacks by dispersing into smaller, more decentralized cells. The group has also replenished leaders killed in the strikes with new even harder-core recruits from Saudi Arabia, Yemen, Somalia and Uzbekistan. The recruits are transiting through Iran and end up in Pakistan's Waziristan region—believed to be Al Qaeda's main base—where the militants receive training, according to the account by Pakistani intelligence officials.

Though less experienced, these new younger recruits were described as even "more dangerous" and determined to foment insurgency inside Pakistan—a potentially ominous development given the weakness of Pakistani President Asi Ali Zardari's government. One apparent sign of that weakness was the recent decision by the Pakistani Army to agree to a truce with the Taliban in the Swat, a region about 100 miles north of the country's capital of Islamabad.

A high-level delegation of Pakistani officials, including military and intelligence chiefs, is currently visiting Washington to discuss antiterrorism operations with the Obama administration.

In a meeting Wednesday with reporters, Leon Panetta, the new CIA director, was asked whether Feinstein's statement about a Predator base in Pakistan had affected counterterrorism operations in that country. Panetta avoided comment on Feinstein's remarks and Predator operations, but did say: "Nothing has changed on efforts to go after terrorists and nothing will change with those efforts ... None of that has diminished and none of it will."

© 2009