Afghanistan a big mess?

Every time I read an article on Afghanistan on nytimes or any other site I’m just left so confused as to what U.S. and NATO troops are doing in Afghanistan. I probably do not know all the nitty gritty details of the all the operations but all I hear is Marjah, Kandahar etc. In this article I read there is comment made by General Carter that says “Afghans will tell you, if you have a peaceful Kandahar, you will have a peaceful Afghanistan.” The General follows that comment up by saying “well only time will tell.” But I feel like the U.S. lacks strategy and goals in Afghanistan. Except for the surge of 30,000 troops ordered by Obama last year to overwhelm the Taliban I haven’t heard of a strategy. I also remember some criticisms of the surge approach, just because it worked in Iraq doesn’t mean it’ll work in Afghanistan and that the situation in Afghanistan is far more complicated. It’s not just Sunni, Shia and Kurds we are dealing with. Then there is the problem of Pakistan and the supposed assistance Taliban receives from the ISI. I wonder if the United States should resort to what Professor Luttwak said the Byzantines might have done if they were in the U.S’s shoes, just arm all the ethnic groups and play all sides and let them fight it out.