A month later, U.S. Army Sgt. Robert Bates allegedly wandered off his remote outpost and went on a shooting spree in an Afghan village, killing 16 Afghan civilians, including women and children, as they slept. It was one of the worst massacres in the decade-long Afghan mission.
In the face of so many setbacks, many say it's Allen's singular ability to connect with Afghans, not as a commanding general but as a human being, that has kept the Afghan mission on track.
When Allen makes appearances alongside his Afghan counterparts, he routinely begins by making eye contact and thanking each of them by name--a mark of considerable respect in Afghan culture. He visits NATO outposts and Afghan troops, trips known as battlefield circulations, at least twice a week. And when he meets rank-and-file Afghan troops, he stops to say "Salam alaikum," the traditional Muslim greeting meaning "peace be with you." He'll even ask them how they're doing, in Pashto.
On Monday's visit to Zabul province, the general spent nearly the entire flight engrossed in ISAF operational updates from across the region, his eyes carefully scanning each page before turning to the next. In his thick-rimmed glasses and deep concentration, he looked every bit the bookworm as he did the "boss."
Later, following a meeting with the provincial governor of Zabul, a southern province that shares a long, mountainous border with Pakistan, Allen was asked why, when he apologized to the villagers of Logar, he referred to himself as a "servant" of the very people whose families the NATO airstrike destroyed.
"My affection for the Afghan people is very great. I feel a great kinship for them.
"I'm here to serve the objectives of the international community, but in accomplishing those objectives, we are serving the Afghan people.
"It's about them. It's about them and the future. So I'm serving them and I serve them proudly."
Perhaps nothing illustrates that more than a simple gesture Allen made during the trip, one so subtle it was missed by most observers.
Moments earlier, as Allen entered the compound to greet the provincial governor, the two held hands as they walked into the meeting hall. The NATO training mission's slogan in Afghanistan is "Shohna ba Shohna" or "shoulder to shoulder."
For Allen, it's also hand to hand.