The argument for reelecting President Obama is not obvious, since the economy is bad, but it’s not all that complex either. I’d say it’s a five-part argument. And tonight, the president finally made all five parts. The big news from this debate will probably be the searing exchange over Libya, but after I shredded Obama’s no-show last time, I should acknowledge that this time Obama actually presented a case for four more years.

Part One is that Obama inherited an ungodly mess, with the economy losing 800,000 a jobs a month and GDP crashing at an 8.9% rate. The president talks about this often, but he drove it home in a new way after Governor Romney noted that gas prices were $1.86 when he took office. Obama shot back (correctly) that gas prices were so low because the economy was collapsing. He then suggested that Romney might restore low gas prices by restoring the policies that collapsed the economy, which is actually Part Four; in any case, it was one of his best lines of the night.

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Part Two is that Obama made the mess better, moving the economy from dizzying job losses to 5.2 million new jobs, from scary contraction to modest growth. He quickly described how his auto bailout took a vital industry from the brink of death to record profitability, arguing that Romney’s prescription of no government aid could have destroyed a million jobs. And he did a decent job of pointing out how his policies have helped people: cutting middle-class taxes by $3600, expanding Pell Grants and child-care tax breaks. I’m biased, of course, but I would have liked to hear him point out that his $800 billion stimulus saved hundreds of thousands of jobs for teachers and other public employees, kept millions of Americans out of poverty and homelessness, provided tens of billions of dollars worth of tax breaks to manufacturers, and created the biggest quarterly jobs improvement in 30 years. But he doesn’t use the s-word.

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Part Three is that congressional Republicans blocked him from doing even more to clean up the mess. I don’t understand why he doesn’t harp on GOP obstructionism—it’s one of the main reasons the recovery has been so weak, and Americans happen to hate Congress—but he did at least mention it tonight. He talked about how he has tried to extend tax cuts for 98% of the country, but Republicans have refused to go along unless the top 2% keeps their tax cuts. He also mentioned Republican intransigence on immigration. But he still could have done more to point out that Republicans have fought just about every policy he mentioned—from student loan reform to infrastructure investments to the Lilly Ledbetter gender discrimination bill. Romney does a nice job talking about his bipartisan work in Massachusetts; it wouldn’t kill Obama to mention every now and then that the Party of No plotted its obstructionist strategy before he even took office. And for the record: He only had a filibuster-proof Senate supermajority for a few months, after Al Franken was seated and the late Arlen Specter switched parties but before Scott Brown’s election.

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Part Four is that Romney represents a return to the Bush policies that got us into the mess in the first place. Obama hammered this point a lot, focusing primarily on tax cuts for the rich, but he probably could use a bit more show and less tell. He did a good job explaining how Romney’s promises of big specific tax cuts along with unspecified loophole-closing and spending cuts are a prescription for huge deficits, but he could have done a better job of linking them to the Bush destruction of the Clinton surpluses. He could have mentioned that Romney shares the anti-regulatory fervor that helped fuel the Wall Street meltdown—and has promised to repeal Wall Street reform. He could also mention that Romney has surrounded himself with the same Bush foreign policy advisers that led America into Iraq.

Part Five is that Obama has basically done what he said he would do. And he slammed home this point when the disappointed former Obama voter asked why he deserves another term, listing a slew of promises kept: middle-class tax cuts, small business tax cuts, ending the war in Iraq, decimating al Qaeda and killing bin Laden, reining in insurance companies and expanding affordable insurance, reforming Wall Street, saving the auto industry, and creating 5 million jobs. At other times in the debate he mentioned that he’s enacted ambitious education reforms—he could have mentioned that many conservatives support Race to the Top—and doubled renewable energy. He could have added that he allowed gays to serve in the military and made record investments in research, and he could have done a better job explaining why he’s failed to keep his promise to cut the deficit in half. (Or at least remind voters that he inherited a trillion-dollar deficit from Bush.) But I liked the way he didn’t pretend everything had gone his way: “Those I haven’t been able to keep, it’s not for lack of trying, and we’re going to get it done in a second term.”

Personally, I didn’t think Romney was nearly as awful in this debate as Obama was in the first debate. I thought he scored some points on the deficit, and I was surprised that Obama often seemed to cede the point that the economy is a mess, when recent numbers have given at least the illusion of improvement. Still, this felt like a solid whupping. And more important, it sounded like a solid case.

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