Anyone watching the presidential debate as closely as I was, and my colleagues who were simultaneously blogging and IM'ing, surely saw dozens of missed opportunities for Senator Obama to take a point or knock down Senator McCain. Why concede that McCain achieved anything on torture? (The CIA is torturing people today.) Why let the economic discussion be diverted into nonsense on earmarks? Why not call out McCain's absurdly Manichean view of the Russia-Georgia conflict? Why let the idea that we've all but won already in Iraq pass unchallenged? Why say, "John is right"? Why not jump on McCain's call for a spending freeze, and its real-life consequences?

Passing up those opportunities might have been a mistake, but it was not an oversight. Obama had plainly made a decision to project the actual knowledge and insight he has on foreign policy (which throughout the campaign has actually seemed to come more naturally to him than domestic and economic policy). The only way to do that is to resist, resist, resist the temptation to take every opportunity for the kill. Obama had a game plan and he executed it. The result is that voters who had not yet appreciated that Obama understood foreign policy, who assumed that McCain was the military/security guy and Obama the domestic, mommy-party candidate, had a chance to recognize that he more than knew what he was talking about -- that he had what sounded like a coherent, responsible, and not-weak vision.

The deep message is similar to that of Obama's two-minute economic ad earlier in the week. It's not to say any particular thing but just to show that you can talk at some length, and assume the voters' intelligence, in a way that inspires general confidence.

After the crazy week, McCain's cancel-the-debate ploy, and his swing-for-the-fences tactics (or is it strategy?), McCain's simple ability to stand calmly and think on his feet was almost surprising. But it shouldn't have been. McCain after all survived two previous meltdowns in his own campaign, without money, and he did it just by being able to think on his feet, and outclass Mitt Romney and Rudy Giuliani. No, he didn't suddenly start talking like Sarah Palin. The moments when he can't decide if Spain is a good country or a bad country (there are no others) are rare.

McCain's line of the day, "he doesn't understand" was a good unifying thread, but most of the time the specific point wasn't really persuasive. And since Obama didn't say anything that fueled the idea that he doesn't understand the world, it seemed more slogan than charge. When you go into a debate with a catchphrase, like Reagan's "There you go again," it helps to save it for the moment when it really applies, not just repeat it all the time.

Obama had a phrase too, although he only used it twice (I thought it was more until I checked the transcript): "21st century," as in "We did not set up a 21st-century regulatory framework to deal with" the economy, or brilliantly deriding Russia for trying to be a 20th-century superpower. That sense of a more modern, advanced, next-generation, but still solid, nuanced vision of America's role in the world was all Obama was trying to convey. And judging from the instant polls, with all their caveats, he did so.

He could have gone for the kill, but it would have been a very different debate and he might have squandered the much more basic, modest goal that he needed to achieve.

--Mark Schmitt.