If President Obama's speech last night at West Point was designed to spell out U.S. objectives in Afghanistan, I thought he did a masterful job. It was a serious, no-nonsense appraisal of the situation, the challenges America faces, the history behind his decision to send an additional 30,000 troops, and how it would facilitate the beginning of a withdrawal in 2011.

But if a nationally-televised address is designed to change minds, to rally a nation behind a policy, then I think the jury is still out. Americans are torn about this war, unsure if victory — whatever that means — is possible, and unsure if it's worth the cost, both in American lives and what it would do to an already weak economy. As it is, the president still hasn't told us how the war will be paid for or how he thinks the Karzai government will turn around or how it affects what's going on in Pakistan, arguably a more volatile situation,

And I thought he missed the point by dismissing efforts to compare Afghanistan to Vietnam. He said such a comparison "depends upon a false reading of history," noting that Vietnam, unlike Afghanistan, never attacked the U.S., among other differences. But the reason people compare the two is the fear the Afghanistan conflict, already approaching its ninth year, will become the "quagmire" that defined Vietnam. And with people on the right insisting that a "timeline" would embolden the enemy, and with people on the left saying no amount of additional troops will remedy the situation there, the speech could turn out to be Obama's brief, shining moment in a war that could very well define his presidency.

Click here to read my study on Presidents, Congress, and the decision to make war policy since Vietnam.