Avishai Margalit in the NYRB blog:
For a war to be just, there must be moral grounds for going to war and moral conduct in the war. Thus, going to war requires having a just cause, whereas correct behavior in the war requires discriminating between combatants and civilians. Obama mentioned both conditions as well as some others. But then there are also conditions that must be met for continuing a war, among them having a reasonable prospect of success. Yet in his Nobel speech, Obama omitted this important condition for continuing the war in Afghanistan. It is not only stupid, but it is also immoral, to go to war, or to continue a war, when there is no prospect of victory. Having the right cause on your side is not enough; your chances of winning are just as important.
As an admirer of President Obama I have listened attentively to his recent speeches on Afghanistan. But at no point has he made a plausible case for how he will win the war. He counts on our taking a leap of faith to support his strategy, but leaps should be reserved for frogs, whereas we should subject our faith to critical thinking.
The main declared objective of the war—defeating al-Qaeda—is not a matter for helmeted marines but for bespectacled bank accountants, computer whiz-kids, and people who can speak the relevant languages. The war in Afghanistan, by now, has very little to do with defeating al-Qaeda. Vice President Joe Biden got it right when he argued that fighting al-Qaeda is not the same thing as fighting in Afghanistan. Moreover, the conflict in Afghanistan bears little relevance to the problem of keeping Pakistan’s nuclear weapons out of the hands of radical Islamists; the Pakistani army is as much of a problem as the Taliban.
Adhering to just war doctrine requires having the right intent for continuing to fight in Afghanistan. Continuing the war out of fear of being accused of not giving the generals the resources they need to finish the job does not count as the right intent.