Our political leadership from Johnson down through most of the US congress - because of the American blind opposition to communism - failed to treat Vietnam as a serious strategic problem. Too many around here would do the same in Iraq. So far, I have yet to find anyone on FR who can tell me what success or failure in Iraq would look like. If Iraq were to be taken over by the Taliban or the Mahdi I would regard that as a failure. The implanting of a christian based liberal democracy (liberal in the traditional meaning of the word), on the other hand, is something beyond earthly powers, so I merely inquire where we plan to stop, and stir up a hornets nest of indignation at the question.
Hagel is a decorated Vietnam veteran and he is asking exactly the same things you are.