BOCA RATON, Fla. — The “horses and bayonets” moment is probably the headline. But the larger story of the third and final presidential debate, ostensibly about foreign policy, is that Mitt Romney didn’t really lay a glove on President Obama. For most of the evening, he didn’t even try.

Obama came ready to punch, Romney to counterpunch — or, since we’re torturing the boxing metaphor, to clinch. He agreed with Obama’s policy on Afghanistan, on Libya, on Syria, on the use of pilotless drones in the fight against al-Qaeda, pretty much on everything except how to improve the U.S. economy. Which wasn’t even supposed to be a topic of discussion, but apparently nobody told the candidates.

The president spent much of the evening recounting Romney’s earlier, contradictory foreign-policy positions — his prior view, for example, that the United States shouldn’t have pressed to oust Libyan dictator Moammar Gaddafi because that amounted to “mission creep.” On that issue, as on many others, Romney simply did not acknowledge his flip-flops. It was as if he were at a dinner party and someone brought up a topic too vulgar for polite company.

Obama had the best line of the evening, when Romney brought up his oft-repeated complaint that defense spending needs to be dramatically increased. The Navy is smaller now, Romney said, than it was in 1917.

“Governor, we also have fewer horses and bayonets,” Obama said. He went on to explain that perhaps we do not need as many conventional ships as nearly a century ago, since now we have aircraft carriers, nuclear-powered submarines and other modern weapons.

Throughout, Obama was confident and sure-footed. Romney was much less so. It was Romney’s weakest performance of the three presidential debates — an instant poll of undecided voters by CBS found 53 percent of those surveyed believed Obama won, compared to 23 percent who gave the nod to Romney — and if anyone gets a post-debate boost in the polls, it is likely to be the president.

Voters who tuned in, however, to hear a sophisticated discussion of the role the United States should play in a fast-changing world were probably disappointed.

This year, in the race for the White House, the debates have really mattered. The issues, not so much.

The most substantive clash, in terms of the economic issues that voters say they most care about, was not between Obama and Romney. At Centre College in Kentucky, Vice President Biden and Paul Ryan talked about jobs, economic growth, deficits and entitlements. They outlined sharp differences in how the two parties see the nation: Biden championed community and compassion; Ryan, individual initiative.

The presidential encounters, by contrast, have been largely about style and presence — who was aggressive, who seemed presidential, who looked his opponent in the eye, who showed a sense of humor, who interrupted whom.

But going into the last two weeks of the campaign, we still have no idea how Romney would manage to cut income tax rates by 20 percent without increasing the deficit. We don’t know which tax deductions he would target for possible elimination, although he did say at the town-hall debate that his plan might be to establish an overall deductions cap and let taxpayers decide which ones to take. He still has not made the slightest attempt to demonstrate that the arithmetic adds up.

We know Romney envisions a future in which the U.S. economy returns to full employment, but we have no real idea how all the tax-cutting he proposes is supposed to get us there. We know he promises 12 million new jobs — but we also know that many economists believe the U.S. economy could add that many jobs in the next four years with no policy changes, assuming the recovery gains a little steam.

We know what Obama has done in office — averting a depression, saving the auto industry, passing health care reform, ending the war in Iraq, killing Osama bin Laden. But we still don’t have a vivid picture of how Obama sees the next four years. He spells out his policies, but he doesn’t tell us where they lead.

Obama won Monday night. As I see it, he still has a slight edge overall. Nothing is guaranteed.

Eugene Robinson’s email address is [email protected] (c) 2012, Washington Post Writers Group

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