A reader sums it up nicely:

I think pretty much everyone is missing the point:  no one knows what ‘victory’ in Afghanistan would look like or how to achieve it.  It is foolish on so many levels to make an open-ended commitment, so Obamaunusual in my viewhas made the right call:  escalate, hopefully inflict substantial casualties on the Taliban and AQ, possibly snag OBL in the process, and then get out on our terms rather than departing in a fashion that looks, to the Muslim world, like retreat.  It is pretty much all we can do and I am glad he is doing it. If there is an off-chance the surge will actually make a difference, that is a bonus.

The moral question is simply whether it is right to send young men and women to die for a couple more years to make an exit less dangerous and more face-saving than simply quitting now.

By giving the military a chance to inflict maximal damage on the Taliban and the CIA lee-way to do the same to al Qaeda within Pakistan, Obama means to achieve maximal weakening of foes before a strategic withdrawal.

Any withdrawal will be met with Romney-Palin-style accusations of weakness, treason, irresolution. But a withdrawal after a big surge is less likely to be successfully targeted in that manner. And after ten years, will Americans really want to keep 100,000 troops in a lunar landscape run by a kleptocracy because that's where al Qaeda used to hang out? The more I think about this, the smarter it is - both militarily and politically.

But that tends to happen with Obama decisions, doesn't it?