ROBERT SIEGEL, HOST:
Insider attacks in Afghanistan have killed more than 50 U.S. and allied service members since the beginning of the year. Now they're having an effect on military operations. The American command in Kabul has temporarily halted joint patrols between U.S. and Afghan forces.
As NPR's Tom Bowman explains, that could complicate America's exit strategy, which depends on training Afghans to handle their own security.
TOM BOWMAN, BYLINE: American troops patrolling with Afghans has been a mainstay of operations in Afghanistan for years now. But now, such patrols have been suspended - there's no word on how long - because of what's been called Green on Blue attacks, gunmen in Afghan uniforms killing U.S. and allied troops. Sometimes they're disgruntled Afghan soldiers, sometimes they're Taliban infiltrators.
JAY CARNEY: While the military continues to work to understand why there has been a spike in the kinds of attacks, so-called Green on Blue attacks...
BOWMAN: That's White House spokesman Jay Carney.
CARNEY: ...we're working with Afghanistan to take measures to better protect our troops.
BOWMAN: One of those measures, Carney says, is a decision by the top U.S. commander in Afghanistan, General John Allen, to suspend the joint patrols.
CARNEY: Most partnering and advising will now be at the battalion level and above.
BOWMAN: A battalion is a military unit of about 600 or more soldiers. Joint operations by units smaller than that are the ones put on hold. Starting this week, it will take a two-star American general to grant any exceptions to the new rule.
CARNEY: The need for that will be evaluated on a case-by-case basis.
BOWMAN: This is the first time that the growing number of Green on Blue attacks have affected operations in the field. Before today, U.S. forces have taken other measures to protect themselves from insider attacks. They now carry weapons at all times, even in meetings with Afghan officials.
Today, NATO Secretary-General Anders Fogh Rasmussen tried to be upbeat about the latest developments. He said the suspension of patrol shows that Afghan forces are becoming more competent.
ANDERS FOGH RASMUSSEN: The fact that it is possible, as a temporary measure, to suspend some partnered activities reflects that Afghan security forces are able to operate on their own.
BOWMAN: But that's not always the case in the field. In May, NPR traveled throughout Afghanistan and found that Afghan soldiers still depended heavily on their U.S. partners. During one patrol in southern Afghanistan, American soldiers took the defensive positions, watching for Taliban fighters, their weapons at the ready. Not 50 yards away, Afghan troops were casual, smoking cigarettes and talking on cell phones.
Army Captain Chris Langteau(ph) who was leading the patrol watched them and smiled.
CAPTAIN CHRIS LANGTEAU: We're still working on the whole, the fundamentals of pulling security. We're still working through a lot of that with them.
BOWMAN: U.S. and NATO officials say the Afghans will be better trained in two years when they're supposed to take full responsibility for their country's security. NATO Secretary Rasmussen says a new suspension of joint patrols won't affect that.
RASMUSSEN: We will continue to hand over in a gradual process lead responsibility for the security to the Afghan security forces. And that process will be completed by the end of 2014.
BOWMAN: Well, not entirely. The U.S. and NATO are planning for thousands of military trainers to remain in Afghanistan well beyond that date.
Tom Bowman, NPR News, Washington. Transcript provided by NPR, Copyright NPR.