The decision President Obama made was better than the speech he gave. What will matter, long after his address is forgotten, is that Barack Obama gave Generals McChrystal and Petraeus, two of our greatest military minds, the troops (30,000, plus additional allied troops) and strategy (counterinsurgency) they need to prevail in Afghanistan.

To the president's credit, this is the second wave of troops he has sent to Afghanistan (in February, he approved sending 17,000). Mr. Obama, in siding with McChrystal and Petraeus, wisely ignored the counsel of his vice president, Joe Biden, whose 35-year track record on national-security matters is an almost unbroken string of unwise decisions. And the president made a decision that puts him at odds with his liberal/left-wing base, which seems as eager to lose in Afghanistan as it was eager to lose in Iraq.

As for the understandable concern some people have about Obama's 18-month time line: it is, at least for now, less worrisome than it might appear. In his speech, Obama said we will "begin the transfer of our forces out of Afghanistan in July of 2011. Just as we have done in Iraq, we will execute this transition responsibly, taking into account conditions on the ground." That is a key caveat; if conditions on the ground change, Obama has left himself plenty of room to revisit his decision. Nothing is etched in stone.

The president wisely backed away from bashing President Karzai, which at this point would only have been counterproductive. The focus on Pakistan was appropriate and intelligently stated. There was a degree of realism and candor about the situation that was impressive. Obama skillfully dispatched some of the concerns about his policy. And the president did something that was, for him, rare: he spoke about human rights and American achievements in a manner that was less than grudging.

At the same time, the speech did almost nothing to advance the public's understanding of what is at the core of a counterinsurgency (as opposed to a counterterrorism) strategy. Obama's remarks were also another instance of his being ungracious and unfair to his predecessor. You would think that given Obama's haplessness on a whole range of foreign-policy issues, he would begin to show a smidgen of humility. Not a chance. In addition, the West Point address was far too self-referential and self-justifying, invoking imaginary achievements (such as forging a "new beginning between America and the Muslim World"; Fouad Ajami explodes that myth here). We were reminded by Obama, several times, that "I do not make this decision [to deploy additional troops] lightly." Nor, he could have added, did he make it expeditiously. And the address included paragraphs that President Bush used to call "cram-ins" - in this instance, a poll-tested section on the economy that was undoubtedly put in by political advisers and that did a fine job of breaking the flow of the speech.

The most worrisome thing about last night, though, is that Obama's statement that "our resolve [is] unwavering" came across as words on parchment rather than a deep, unwavering commitment. Will he hold shape if the summer of 2010 turns out to be a difficult and bloody one, as it may very well be? I hope so, and I choose to believe so. Will he continue to make the case for this war publicly and repeatedly, to explain to the citizenry why this conflict is worth waging and winning? We shall see. These are open questions. But one cannot help but get the sense that Obama is dealing with Afghanistan only with great reluctance, that he views it as an unwelcome distraction from his domestic agenda. He does not seem to view this war in the context of any great cause, whether it is the liberation of captive peoples or prevailing against men of almost unimaginable cruelty and malevolence. The president came across last night as clinical and detached, somewhat distant and weary. He seemed to be reporting to the nation rather than trying to rally it. You do not sense that this is a man whose heart has been touched by fire.

In the end, though, Obama's decision will, I think, turn out to be far more important than his words. Having been given the tools, the exceptionally skilled McChrystal and Petraeus, backed up by the greatest fighting force on earth, can finish the job. They at least have a fighting chance, thanks to their commander in chief. At this juncture, that's about as much as they, and we, could ask for.

Peter Wehner is a senior fellow at the Ethics and Public Policy Center in Washington, D.C. He served in the Bush White House as director of the office of strategic initiatives.