When Do We Leave?

On Afghanistan, I wrote that  "Obama's pledge to start withdrawing troops in 2011 is now kaput ... Once Washington has decided to occupy a country, it will occupy it for ever." Max Boot says I was battling a strawman:

I hope Andrew is right not because I or anyone else is in favor of perpetually occupying Afghanistan (talk about a straw man!) but because the only way to prevail is to show the will to stay in the long run.

[Boot] conveniently declines to specify what the long run is. But why? If Boot thinks the way to leave Afghanistan is to never say we're going to leave could he at least proffer a guess as to when the U.S. will have achieved its goals in the country sufficient enough to stop transferring American wealth and risking American and NATO lives in the country?