BOCA RATON, Fla. — President Barack Obama and Republican Mitt Romney spent their final debate Monday circling the globe’s hot spots as they clashed over the merits of diplomacy and brinkmanship in Libya, Israel, Iran, the Middle East and other volatile areas.

[Click here to watch the full debate]

But they also managed to get in digs at their opponents’ economic plans.

The topic of the 90-minute clash at Lynn University was foreign policy, which polls show is not a major concern of most Americans as they prepare to vote Nov. 6. About one-third of the way through the debate, Obama and Romney turned the talk to the economy, the issue that is overwhelmingly most on voters’ minds.

A strong America, Romney said, must have a strong economy. “America must lead and for that to happen we have to (fix) our economy here at home,” he said.

Obama, too, wanted to talk about the economy. He talked about education – a topic rarely mentioned during the first two debates – and charged that Romney’s policies would do little to reduce class sizes and support teachers. Slashing support for education “is not good for America’s position in the world, and the world notices.”

Romney cited his record as governor of Massachusetts from 2003 to 2007, arguing he supported teachers. Obama tried to interrupt and charge Romney was not so generous to education.

The debate’s main purpose was to give voters a measure of how each candidate would act as commander in chief, and both men tried to portray themselves as resolute as well as reasonable.

Obama charged that Romney was tied to policies of the past. “Every time you’ve offered an opinion, you’ve been wrong,” the president said.

Romney, he explained, wanted more troops in Iraq and has a confused, changing Afghanistan policy.

What’s needed is “strong steady leadership,” Obama said. Romney’s plan, he added, “is not a recipe for American strength.” The president recalled Romney’s characterization of Russia as a major U.S. foe.

“The ‘80s is calling, asking for its foreign policy back," Obama said,

Romney fought back. “Of course I don’t concur with what the president said about my own record. They don’t happen to be accurate,” Romney said. “Attacking me is not an agenda. Attacking me is not (how to) deal with challenges in the Middle East.”

The debate began with Obama vigorously defending U.S. policies. “It’s important to step back and think about what happened in Libya,” Obama said. He recalled how the U.S. “organized an international coalition,” without involving U.S. troops on the ground, which helped topple the regime of Moammar Gadhafi.

“I have to tell you that your strategy previously has been one that is all over the map” and not equipped to help American interests in the Middle East, he said.

Romney labeled his strategy “straightforward.” The major strategy, he said, is to “make sure we go after leaders of these various anti-American groups and these jihadists.”

Romney began the debate methodically recalling the turbulent events of the last few years. “What we’re seeing is a pretty dramatic reversal of the kind of hopes we had for that reason,” Romney said.

“But we can’t kill our way out of this mess,” he said. “We’re going to have to put in place a very comprehensive and robust strategy to help the – the world of Islam and other parts of the world, reject this radical violent extremism, which is – it’s certainly not on the run.”

Obama cited his record, saying al Qaida’s leadership had been “decimated,” and how his policies have allowed the United States to rebuild alliances and combat future threats. One way to do that, he said, was to push more economic development, education, gender equality and adherence to the rule of law.

Some of the other topics at Monday’s debate:

– Military spending: One way to show American strength, Romney argues, is to beef up military capability. Before leaving for a pre-election recess, Congress agreed to set defense spending for fiscal 2013, the 12-month period that began Oct. 1, at about $519.9 billion, about the same as last year.

Automatic cuts planned to begin in January would shave about 9 percent to 10 percent from most Pentagon programs this year and $500 billion over 10 years. Romney says he’ll stop those cuts, but does not say specifically how he’d do that without increasing federal deficits.

Such cutting, he said, “is making our future less certain and less secure.” Obama noted that the automatic cuts are “not something I proposed” and vowed they would not happen.

Romney reiterated his complaint that under Obama, the Navy is at its lowest number of ships since 1916.

Obama ridiculed the remark, saying the U.S. military needs have changed. "We have fewer horses and bayonets," he said. "The nature of our military has changed. This is not a game of ‘Battleship’ that we are playing."

--Syria. Neither saw a role in Syria for the U.S. military. But Romney criticized Obama’s approach, accusing the administration of not taking a leading role in ousting President Bashar al-Assad. "This should have been a time for American leadership," he said, calling for the U.S. to identify Syrian insurgents it could help.

Obama countered that the administration has led an effort to get humanitarian aid to the Syrians and help to the rebels.

"We are playing a leadership role," he said.

– Iran: Obama vowed that as long as he’s president, Iran will not get a nuclear weapon. “A nuclear Iran is a threat to our national security and it’s a threat to Israel’s national security,” he said. Romney said much the same thing Monday

He also said “crippling sanctions” against Iran work. “I would tighten those sanctions,” he said. “I’d take on diplomatic isolation efforts.”

Aside from putting greater stress on threatening military action, Romney hasn’t articulated a plan for dealing with Iran’s nuclear program that’s much different from Obama’s approach. That policy combines tightening sanctions and keeping a military option open while pushing for a diplomatic deal under which Iran would halt its enrichment of uranium.

While there have been U.S. sanctions on Iran for decades, Obama succeeded in winning Chinese and Russian support for additional U.N. measures and has coordinated a growing menu of harsher measures with the European Union. The combined steps, the toughest sanctions ever imposed on Iran, have severely slashed Iran’s oil export earnings, made it harder for Tehran to import nuclear-related materials, reduced the Iranian central bank’s access to hard cash and helped plunge the value of the rial by 80 percent in the last 10 months.

Iran has continued to expand its uranium enrichment program in defiance of U.N. resolutions. But Iranian leaders have in recent weeks called for the United States, the European Union, Russia and China to resume stalled negotiations on a diplomatic deal, and a new round is expect late next month.

– Iraq and Afghanistan: Romney has echoed Obama’s goal of withdrawing combat troops from Afghanistan by the end of 2014, but he said he’d let military commanders determine the pace. And Republicans have criticized Obama for failing to secure an agreement with Iraqi leaders to keep some peacekeeping forces in that country.

Romney has charged that the troop withdrawals were “based upon electoral expediency, not military requirement,” though polls have shown that most Americans support the move. Additionally, the American troop withdrawals from Iraq were required under a timetable negotiated by the Bush administration before Obama took office.

– Israel: “I will stand with Israel if it is attacked,” Obama pledged. “If Israel’s attacked, we have their back,” added Romney.

Romney has known Prime Minister Benjamin Netanyahu since they worked together at a Boston consulting firm in the 1970s, and they visited in Israel earlier this year. Romney has frequently criticized the relationship between Obama and Netanyahu.

Jonathan S. Landay and Kevin G. Hall in Washington contributed.

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