Yeahhhh Afghanistan was a shitshow. We were actually nation-building, not just nation rebuilding like we did in Iraq, a lot harder to create a national identity out of several tribes and ethnic groups than it is to change/"modernize" a nation like we did in Iraq.
Even Iraq had that issue with the sectarianism, but atleast almost everyone spoke the same language (sorry Kurds). Iraq had also had a national identity beat into them by the monarchy and then the Baathists, which probably helped as well.
Afghanistan never really had that.