On paper, the path out of Afghanistan for the U.S. remains what it's always been: preparing Afghan troops to fight the insurgency by 2014. And the NATO military command insists that's all on course. But in reality, the persistence of Afghan troops attacking their American mentors has prompted a major shift in how the U.S. trains Afghans, to the point where it calls into question the cornerstone of the U.S. exit strategy.

From now on, if you're a U.S. platoon leader or a company commander, you need the express approval from a two-star general if you want to conduct an operation with Afghan forces. You might also have been told that training those Afghans was among your top priorities during your deployment, if not your first priority. Now there's a thick layer of bureaucracy between you and that mission.

"This makes sense if you're sitting up in Kabul at [NATO] headquarters," says Matt Zeller, a captain in the Army Reserve who spent 2008 in Ghazni province as a lieutenant training Afghan soldiers and police. "It makes no sense if you're on the ground."

No one yet knows how this will play out in practice. The change, issued Sunday by the NATO command, doesn't affect interaction between the U.S. and Afghan security forces at the battalion level and higher, which is useful for planning. But, as the New York Times reports, the shift "would sharply limit organic cooperation between junior American and Afghan officers and their troops in the field," which is where the "partnering" mission moves from slides on a PowerPoint to reality.

A Tuesday morning statement from the NATO command, known as the International Security Assistance Force or ISAF, insisted there was no actual change taking place. "In response to elevated threat levels resulting from the 'Innocence of Muslims' video, ISAF has taken some prudent, but temporary, measures to reduce our profile and vulnerability to civil disturbances or insider attacks," the statement reads. But it does not indicate how temporary the shift is. Protests related to the video may subside, but so-called "Green on Blue" attacks of Afghan troops on American ones don't appear as temporary.

ISAF faces a terrible dilemma. At least 40 U.S. and allied troops have died at the hands of their ostensible Afghan partners since the year began. And now, attacks using the anti-Islam "Innocence of Muslims" video as a pretext have spread to Afghanistan. A dramatic assault on a remote Marine Base in Helmand Province on Saturday killed two Marines and destroyed six Harrier jets. The attack was supposedly a response to the video. So it's not as if ISAF isn't responding to a very real problem here – indeed, whenever an Afghan soldier kills his American counterpart, the media is quick to demand ISAF explain what it did to protect its troops.

But the new directive raises major questions about the future of U.S. mentorship to the Afghans. U.S. troops have been directed to bring the Afghans along on practically every mission they conduct – missions that almost always occur at the company and platoon level. In August, Marine Gen. John Allen, the ISAF commander, told the Pentagon press corps that "what we have learned is that the closer the relationship with them – indeed, the more we can foster a relationship of brotherhood, the more secure that we are." Indeed, it was Allen who directed ISAF troops last year to make training the Afghans their top priority.

And it's not just operations. In many cases, the Afghans physically live with their U.S. mentors, particularly on small bases sized for a company. Placing a layer of bureaucracy between Americans and Afghans will occur while those two forces share dining facilities and see each other every day. "Do you, all of a sudden, ignore the company commander you've worked with?" wonders Zeller, who lived on one of those bases, called Forward Operating Base Vulcan, with Afghans. "I would sympathize if [Afghans] felt abandoned."

Then there's the question of the training. Training Afghan troops doesn't happen in a classroom. It happens on joint patrols, and often under fire. Few Afghan battalions operate with sufficient proficiency, in the judgment of ISAF, to act independently. And last year, defense wonks from the Center for a New American Security returned from a trip to Afghanistan lamenting that U.S. commanders were so focused on fighting the Taliban that their instinctive impulses were to put training Afghans on the back burner. Restricting low-level interaction with the Afghan soldiers has real risks for the progress of those Afghans.

One thing hasn't changed, however: the 2014 date for ending the U.S. combat mission and turning the war to the Afghans. It's President Obama's policy, endorsed by Republican challenger Mitt Romney. What ISAF is doing to restrict low-level mentorship calls into question how prepared the Afghans will be to combat the insurgency the day after the handover.