By Adam Levine, with reporting from Nick Paton Walsh, Masoud Popalzai, Larry Shaughnessy, Moni Basu, Chris Lawrence and Tim Lister
The gunman who shot two U.S. military officers on Saturday in the highly secured Afghan Ministry of Interior was a junior intelligence officer with ties to a Pakistani religious school, an Afghan counter-terrorism official said.
It's just the latest incident of "green on blue" attacks which have been a rising problem for the U.S. and NATO. A recent Congressional hearing looked at the issue and found that while some were influenced by Taliban ideology, some of the motives were more personal.
It adds another layer of difficulty to tamping down the anger and mistrust that has arisen from the admission by NATO that troops burned some religious documents seized from prisoners.
The fallout has led to violent protests. Through the end of 2011, existing security procedures failed to identify 42 attackers between 2007 and 2011, all members of the Afghan National Security Force, according to military data released at a recent congressional hearing . Three other attacks were perpetrated by contracted employees. There have been a number of incidents in the first two months of 2012.
The incidents are a mere fraction of the total coalition deaths in the war. But they may feed a climate of uncertainty and even mutual suspicion between Afghan units and their coalition partners at a time when NATO's International Security Assistance Force is trying to hand over control of more districts and provinces to the Afghan National Army.
Saturday's killing of the American officers prompted Gen. John Allen to order several hundred ISAF advisers to withdraw from ministries in Kabul as a precaution, raising more questions about a U.S. military plan that plans to focus on the use of small teams of military advisers as it withdraws troops.
The defense officials appearing at the hearing of the House Armed Services Committee earlier this month said that in 58% of cases, the attackers were not puppets of insurgent groups but acted on their own accord, perhaps over a personal dispute.
Such disputes can arise from cultural misunderstanding, religious and ideological friction or combat stress, said Brig. Gen. Stephen Townsend, director of the Pakistan/Afghanistan Coordination Cell in the Joint Chiefs of Staff office.
He said cultural training has been vital for U.S. soldiers, and now the Afghans are considering doing the same in providing better understanding of Americans.
Another chunk of perpetrators involved insurgents who were able to pass themselves off as Afghan soldiers and infiltrate bases.
David Sedney, deputy assistant secretary of state for the region, said the greater the partnership between Afghans and coalition troops on providing security, the greater the risks are to Americans. At issue was also the problem of Afghan soldiers turning on one another and on civilian populations.
"No system is perfect ... but no system is static," Sedney said.
Earlier this year, Air Force released its investigation into a 2011 killing of eight American airmen and a security contractor by an Afghan air force officer.
The probe raised questions about the relations of American and other NATO troops to their Afghan counterparts.
The Afghan air force officer, Ahmed Gul, had declared his desire to kill Americans, behaved erratically at work and frequented a mosque known for its anti-American views.
The report suggested that Gul, though acting alone, was influenced by jihadist ideology and also suffering from financial strain.