Yep, in Vietnam we made the South Vietnamese change their government from a mandarin style into a democracy while a war was going on. The Romans created and ruled their Empire which lasted 500 years or so because once they conquered a people, a nation, a state, they let them basically government themselves, maintain their culture and traditions with a Roman overseer to collect the taxes due Rome. They did not try to change the people into Romans, they let them be themselves to be ruled locally by their fellow tribesmen or countrymen.
We accomplished our original mission pretty darn quick, within a couple to few months. We with air power and the Afghani on the ground drove out the Taliban thus stopping the training grounds and safe havens for AQ. We didn't get UBL, but the Northern Alliance, a group of tribes allied together against the Taliban were our friends. We could have let them set up their local government as they wanted and saw fit. Keep our air power at the ready and let the Afghani fight on the ground. But those in power here thought they new better and started this nation building stuff which was nothing more than forcing our type of government upon those who didn't want it. Now we are left with what we have, most likely a nation that will revert in the near future to what they originally wanted once the Taliban were driven out. Except this time, the Taliban is coming back and probably quite a lot of those tribes that fought to drive them our, will be fighting by their side to return them power. What a mess nation building has caused.