I have a hunch about what happened here but I’m interested in hearing from military readers. Is this SOP when the SecDef or some other bigwig comes to speak to you at a base?

CAMP LEATHERNECK, Afghanistan — Defense Secretary Leon E. Panetta landed here Wednesday morning for an unannounced and tense visit, the first by a senior member of the Obama administration since an American soldier reportedly killed 16 Afghan civilians, mostly children and women…

In a sign of the nervousness surrounding Mr. Panetta’s trip, the Marines and other troops who were waiting in a tent for the defense secretary to speak were abruptly asked by their commander to get up, place their weapons — M-16 and M-4 automatic rifles and 9-mm pistols — outside the tent and then return unarmed. The commander, Sgt. Maj. Brandon Hall, told reporters he was acting on orders from superiors.

“All I know is, I was told to get the weapons out,” he said. Asked why, he replied, “Somebody got itchy, that’s all I’ve got to say. Somebody got itchy; we just adjust.”

When I first read it I thought they were worried that a U.S. soldier might go berserk and try to frag Panetta, as if the rampage last weekend against Afghan civilians had suddenly called the stability of the entire force into question. That would be a terrible insult to American troops — but I don’t think that’s what they were concerned about. More from the AP:

Afghan troops had already been told not to bring their guns in.

“Something has come to light,” Sgt. Maj. Brandon Hall told the troops. It was a highly unusual order, and some in the audience said they had never seen that happen before…

The official said the decision was made out of respect for troops from other countries, such as the Afghans, who are never allowed to bring guns into an event. It was not a request from Panetta or his security team, the official said.

My hunch: They were worried that an Afghan soldier, not an American, might try to kill Panetta, which is a totally reasonable fear. But since they’re desperate to rebuild trust between U.S. and Afghan forces after the Koran-burnings, the subsequent fraggings of American troops, and then the rampage on Sunday, they didn’t want to make their distrust of the Afghans conspicuous. So they decided to lay down a “no guns for anyone” rule to make it seem evenhanded. Could be that they’d also gotten a tip that an attempt on Panetta’s life was planned. According to UK news sources, a suicide bomber made it onto the runway as his plane was landing at a British base this morning and managed to set himself on fire in the attack. (Panetta was unharmed.) If they suspected something was coming but didn’t know how, little wonder that they’d want the guns out of Afghan hands. Disarming the Americans too is simply a smokescreen for that goal.

Or maybe I’m wrong and the White House really does think U.S. troops are, to a man, a rampage risk. In that case, they’d better come home a lot sooner than expected. And according to the NYT, they just might.

Update: A commenter notes that the AP piece says Afghans are never allowed to bring guns into an event like this. Right, but my point is that the White House and NATO are suddenly desperate to rebuild the trust between the two forces that’s been deteriorating over the last month. In the past that was less true so they might have been less sensitive to the implicit insult in saying that Afghans can’t be trusted with guns around an allied official. Disarming everyone, U.S. troops included, is a way to eliminate that slight.

Update: Helmand’s top NATO commander says he wanted to be evenhanded:

General Gurganus told reporters later that he had wanted a consistent policy for everyone in the tent, and that “I wanted to have the Marines look just like their Afghan partners,” noting, “You’ve got one of the most important people in the world in the room.” He insisted that his decision had had nothing to do with the massacre; later, defense officials said the decision had had nothing to do with the truck at the airfield.

An e-mailer makes a good point too. An Afghan soldier could surprise an American soldier by grabbing his sidearm and squeezing off a few shots before he’s taken down. The worry here, again, is the Afghans fragging Panetta, not our own guys.