The U.S. Role in Afghanistan in post 9/11 era

In the context of 9/11 and the ongoing war against terror, the US role in Afghanistan has transitioned from Bush's engagement to Obama's end game for Afghanistan. This transition has been put forth in the form of the US-Afghan exit strategy and the US-AfPak policy. Both these policies cum strategies do not only affect the state of Afghanistan alone but also the other state regional stake holders in this region. One of the primary affected parties in this Afghan quagmire is Pakistan which has a major stake in the peace and stability of Afghanistan.