WASHINGTON — A U.S. offensive in Syria against the radical Islamist group that beheaded an American journalist would likely be constrained by persistent intelligence gaps and an inability to rely on fleets of armed drones that have served as the Obama administration's signature weapon against terrorist networks elsewhere, the Washington Post reported Saturday, citing unnamed U.S. officials.
The Pentagon has conducted daily surveillance flights along Iraq's border with Syria in recent weeks as part of a push to bolster U.S. intelligence on the Islamic State in Iraq and Syria without crossing into Syrian airspace and risking the loss of aircraft, the officials said.
The CIA has also expanded its network of informers inside Syria, largely by recruiting and vetting rebel fighters who have been trained and equipped at clandestine agency bases in Jordan over the past two years, U.S. officials said.
Still, senior U.S. intelligence and military officials — speaking to the Washington Post on the condition of anonymity to discuss sensitive operations — said American spy agencies have not yet assembled the capabilities that would be needed to target ISIS leaders and provide intelligence with enough reliability to sustain a campaign of strikes.
"Our intelligence is improving since we began devoting the resources to doing that, but we still have only modest visibility into what is going on in Syria," said Rep. Adam Schiff, D-Calif., a member of the House Intelligence Committee.
A senior U.S. intelligence official said that it would probably take months to build up the necessary intelligence to expand the U.S. air campaign under way in Iraq to ISIS positions in Syria.
The Obama administration has counted on Predator and Reaper aircraft to carry out hundreds of strikes against al-Qaida targets in Pakistan and Yemen, countries where it has at least tacit permission to fly armed drones. The planes conduct near-constant surveillance over extensive territory in both countries and often spend days tracking targets before a missile launch.
But the use of drones is far riskier in Syria, where the forces of President Bashar Assad guard the country's airspace with missile batteries and fighter aircraft. ISIS seeks to overthrow Assad, and strikes against the group would be in his interest. But allowing American drones to reach cities such as Raqqah — an ISIS stronghold — would also probably be seen by Assad as a threat, in part because such aircraft could gather valuable intelligence on his forces.
U.S. officials stressed that Obama has not made a decision to launch strikes in Syria, an action the administration has avoided since the start of that country's civil war. But the video-recorded execution of American journalist James Foley this past week has prompted a re-evaluation of the threat posed by ISIS, an al-Qaida offshoot that holds other American hostages and controls territory across northern Iraq and Syria.