WASHINGTON -- President Obama's decision on Afghanistan was tardy, messy -- and courageous.

In contrast to the expectation that he would settle on a timid half-measure, Obama took more of a seven-eighths measure, leaving his commanders impressed and satisfied. In contrast to former Vice President Richard Cheney's charge that Obama is making national security decisions for "small 'p' political reasons," the president opposed his political base. There is no credible explanation for these actions except a commitment to the national interest. It is time to rally around the president.

Obama's failure -- which is small beside his admirable decision -- has been a failure of communication. During 34 long minutes at West Point, he did little to describe how the troop surge will proceed, and why it could succeed.

Military leaders in Afghanistan make the case better. The source of their confidence is simple: In areas where coalition forces provide effective security, communities respond well -- cooperating with outsiders and rebuilding their own institutions of tribal self-government. But there are not enough of these stable communities, because there are not enough troops on the ground.

In places without security, the Taliban rules by intimidation. Locals receive "night letters" threatening harm and death if they work with the coalition or with cooperative mullahs. Delivered in the dead of night, these notes are often effective.

Eventually, Afghan forces must be able to provide an atmosphere of stability. Which is why the military training component of the surge is so important. This is not a classroom exercise. It consists of American forces partnering with Afghan units -- transmitting knowledge and providing examples of professionalism. Afghan soldiers work hard to impress and emulate their American counterparts. And these partnerships also fight corruption. It is more difficult to be on the take when someone is watching.

The surge in Afghanistan will unfold differently than the one in Iraq, where the enemy held a number of safe havens around Baghdad and in Diyala province. The American military knew that a few additional brigades could flush them out and protect civilians. Some large-scale operations in Afghanistan will be similar. But every valley in Afghanistan's Pashtun east and south has its own story, with locals fighting for different reasons. The effort to pacify these areas will be selective and difficult. Continued...