Last week's suicide bombing that killed seven CIA officers in Khost, Afghanistan, underscores just how difficult a mission the agency and the U.S. as a whole faces in the country. Given the size of the CIA, the loss it suffered when a Jordanian assumed to have been an asset penetrating al-Qaeda instead detonated an explosives belt at a gathering of agency personnel, was the equivalent of the Army losing a battalion. It was a major setback for the CIA after eight years at war, not to mention the fact that it coincided with a moment when the Agency is under political attack in this country on issues ranging from torture to intelligence failings prior to the Christmas Day airline-bombing plot. But the Khost attack is also evidence of the intelligence nightmare we face in Afghanistan, where al-Qaeda and the Taliban, which controls much of the territory, are able to blind the U.S. mission on the ground by continuing to run suicide bombers at us.
To put the attack in context, what we need to understand is that it is not the CIA's standard operating procedure to bring informants into bases, as was done with Humam Khalil Abu-Mulal al-Balawi in Khost. Under more favorable circumstances, the CIA's field officers always prefer to meet with informants one on one and in carefully scouted, out-of-the-way places chosen to protect the anonymity of the informant. But things have to be done differently in Afghanistan, where the CIA has a well-grounded fear that its operatives will be kidnapped or killed a risk that applies to all Westerners in that country. As a result, informants, none of whom can be completely trusted, either have to be met by agents accompanied by security personnel or brought onto a base, behind the wire. (And both those scenarios raise the informant's risk of exposure.)
The painful fact is that the Taliban's growing influence in the countryside has severely narrowed the CIA's field of operations. And although no one has said as much, the purpose of al-Qaeda's attack on the CIA in Khost was to force it to retreat. The agency has vowed to fight on all the harder, and it will do so. But the attack in Khost will force the CIA to draw back farther and farther behind the wire in order to protect its officers. The CIA is a civilian organization that's not built to sustain casualties like this, no matter how willing its employees are to serve in dangerous places like Afghanistan. And replacing the expertise of some of those lost in the bombing will take many years.
The consequences of the Taliban's expansion are unmistakable. Shortly before the Khost bombing, the U.S. military chief of intelligence, Major General Michael Flynn, wrote in a report subsequently made public, "Eight years into the war in Afghanistan, the U.S. intelligence community is only marginally relevant to the overall strategy." His report went on to say that U.S. intelligence is "clueless" and "ignorant."
One of the remedies recommended by Flynn was for operatives to spend more time outside the wire, but the painful truth is that anyone who ventures outside the wire, from the Provincial Reconstruction Teams to routine patrols, is a potential target. It's impossible to profile suicide bombers, and there is no way to avoid them except by holing up on bases.
The question the Obama Administration should be asking itself is this: If the enemy in Afghanistan is able to expand its reach and drive us into crusader-like castles, force us to travel by helicopter and resupply the military with C-17s, is there any chance of turning this around?
Baer, a former Middle East CIA field officer, is TIME.com's intelligence columnist and the author of See No Evil and, most recently, The Devil We Know: Dealing with the New Iranian Superpower