As a military force? No. As a economic development force? Yes.
The problem with the Americans is that they are too near sighted. Recently ISAF agreed to let the Warlords in the North of the Country from Mazar to Badakshan provide security to the people. In essence you are going back to what they refer here as the Mujahideen days.
The period before the Taliban, where the Warlords had their own small kingdoms and ran the governments as they wished. They have absolutely no control in any area south of Pansher and Herat. All the Pashtun areas are essentially at war with ISAF.
That doesn’t mean they have not done good work. Where there is safety and security they have built dams, provided electricity and more importantly basic freedoms that every human being deserves.