I am glad we're leaving. Who can honestly say they thought things would change there because of a rotation of warriors? Warriors don't go and merge into the culture. Our soldiers dreamed of returning home, not staying; or even if they wanted to stay we wouldn't let them. We never conquered the place, so we shouldn't have stayed. There was always going to be a time like this when the forces would have to be recalled and a result similar to this.
Yes, although I guess the key question is: What now? Should we try to learn something from this, so that we can refrain from making future mistakes? That seems to be our main problem, that we don't learn anything from any of our past failures.
One thing that I would note, at least when looking over the successes and failures of US foreign and military policies, is that our leaders may have misapplied policies which ostensibly worked to gain hegemony over Latin America, but didn't work when those same policies were applied in East Asia or the Middle East. They might look at Iraq or Afghanistan and think "oh, it's just another banana republic" and reach rather superficial and specious conclusions about what they're dealing with.