The vast majority of Americans have to take arguments about Afghanistan more or less on trust. We just don't have enough experience there to speak with confidence about tribal relations, or the possibilities of national coherence, or the effects pro and con of injecting more foreign troops, or the many other factors that matter in shaping America's policy. This is true to a degree on all questions of international relations. But it is particularly acute here because the Obama Administration's decision to increase the U.S. commitment, ostensibly en route to decreasing it, rests fundamentally on two judgment calls:
1) Whether Al Qaeda/related terrorist groups really do depend so heavily on a specific geographic base in Afghanistan that, if the U.S. can disrupt them there, we won't have to apply similar efforts later on in Pakistan, Yemen, Somalia, or anyplace else.
2) Whether a limited increase in U.S. troops, for a limited amount of time, really can make a decisive difference -- in the long-term stability of the Afghan regime, in the competence of the police and military, in the resistance to a Taliban or terrorist return, and so on, after allowing for any friction or hostility created by the additional presence of U.S. troops.
I am no expert on either point.* But I know these things: for Obama's strategy to pan out, the answer on both calls had better turn out to be Yes. And my observation of the world over the years makes me assume, fear, and expect that the answer to #2 is going to be No. That is what I meant just after the speech in saying, "I hope he's right." The alternatives are grim.
* On the first point: People I respect strongly argue exactly contrary cases. For instance, six weeks ago Matthew Hoh stressed in his resignation letter that the logic of fighting in Afghanistan, "if honest... would require us to additionally invade and occupy western Pakistan, Somalia, Sudan, Yemen, etc." Yesterday on NPR Andrew Bacevich made a similar case: we were going to the source of the Al Qaeda problem circa 2001, which may or may not have anything to do with the problem ca 2011. On the other side, genuine experts on Afghanistan like Steve Coll have argued that the circumstances in that region truly are unique, and that a disruption of terrorist activities there would make a significant difference.
Again, for this strategy to work, both assumptions have to prove true: the goal must be attainable (#2); and once attained it must prove sufficient and effective in addressing the underlying problem (#1). We're back in the realm of hope.