Our mission in Afghanistan

A stranger comes up to you and punches you in the nose. The stranger looks ready to do it again. Given that you cannot run away, what do you do? You defeat the attacker in such a way that not only will he not be able to attack you again but no one else will want try. If someone helped that person attack you, you defeat them in the same manner. If someone helped them help the attacker you defeat them the same way.
Much of today's news is taken up with the report on the corruption in the Afghan government and its possible effect on withdrawal of NATO/American troops. I have not read President George W. Bush's book so I cannot speak to what he had in mind when we went into Afghanistan but it should have been to destroy the Taliban. To destroy them not because they were (by our standards) miserable rulers, but because they were guilty of aiding and abetting the murder of 3,000 Americans.
Under the American system of justice, if you assist in the execution of a crime you are guilty of that crime. For example if you drive the getaway car from a bank robbery in which a murder is committed you are guilty of murder. Reason for being in Afghanistan should be to kill or capture any and all Taliban, not to involve our selves in internal politics, except as it affects our primary mission. To be clear, current reports state that President Karzi, members of his family, cabinet, and government have funneled money and perhaps other support to the Taliban. They should be subject to being captured or killed immediately.
We are at war with the Taliban and their supporters and the Congress should formalize that reality.