Afghanistan Civil War Unlikely, U.S. Official Claims

"He (Karzai) needs to be confident that whoever succeeds him is not going to trump up some capital charges and have him tried, imprisoned or worse," Crocker said. The ambassador did not elaborate on what offenses a successor might allege against Karzai after he leaves office. - U.S. Ambassador Claims Afghanistan Won't Plunge Into Civil War - Afghanistan
U.S. role in Afghanistan has had positive effects - Trudy Rubin