Krauthammer is right IF you accept his premise that the Iraq of our democratic dreams in perpetuity, was a viable goal. At this point I think it fair to say that most people - including a heckuva lotta righters, have accepted that that goal was not viable. One "tell" is that nobody - to include Krauthammer - is suggesting specifically what a large troop presence on the ground today, should be doing.
The best "gain" we can hope for in this part of the world - and it is a significant one, is to maintain a "presence". For instance those 300 "advisors"?....C'mon, who actually believes that they're advisors? They're information gatherers, pure and simple. And, this is one heckuva lot more access than we had before we invaded Iraq.
The same is true in Afghanistan. I think most of us have come to accept that there's no way we're going to turn Afghanistan into some sort of democratic utopia. What we can do though, is position "eyes and ears" inside Afghanistan if only to monitor events as they effect us.
On a sidenote, conventional wisdom is finally coming around to the fact that these terr'st organization are notable "top down". It makes way more sense to drone their #1, #2, #3 or whatever, than go into the field to shoot at terr'st grunts and have them shoot at us.