Republicans angling to recapture the Senate and White House have focused almost exclusively on jobs and the economy. But with an uptick in violence in Afghanistan and uncertainty in the Middle East, foreign policy could be thrust back into the national debate.

Thus far, President Barack Obama has gone largely unchallenged on his foreign policy credentials. His lack of experience was viewed as a weakness in 2008 when he was running against Vietnam veteran and Senate Armed Services ranking member John McCain (Ariz.).

But Obama has been able to largely avoid or dismiss criticisms of his policies abroad after scoring several foreign policy and military successes. Those include the killing of al-Qaida chief Osama bin Laden, the ouster of Libyan dictator Moammar Gadhafi with help from NATO forces and the fulfillment of a campaign promise to withdraw troops from Iraq.

As November inches nearer, however, Republicans could try to make a case using Iran, Israel, Syria and Afghanistan to create more separation between themselves and the president, especially if the economy continues grow stronger.

“I think the president is doing such a good job — a solid job — on foreign policy that the Republicans haven’t found any particular chink in his armor. If they could, they would, believe me, exploit everything we’ve seen,” Senate Armed Services Chairman Carl Levin (D-Mich.) said. “Anytime they can, they’re trying to criticize the president.”

But Levin was more circumspect when asked whether Republicans could leverage the situation on the ground in Afghanistan, where a half-dozen U.S. troops were killed in a span of eight days after U.S. soldiers burned copies of the Quran at a military base in the country. “I hope not, obviously,” he said.

Levin noted that increased violence in Afghanistan would not affect the preliminary phases of the administration’s drawdown plan — which would withdraw the remaining 23,000 “surge” troops from the country by the end of September — but he said what happens after that is still under discussion.

That drawdown is scheduled to occur just weeks before Election Day, and the situation could remain fluid through then.

“What we’ve seen is how foreign policy can intrude itself into our plans here in unpredictable sorts of ways that change the conversation,” National Republican Senatorial Committee Chairman John Cornyn (Texas) said. “Obviously, we’re all very concerned about what’s happening in Iran and with some of their threats.”

Concern has been growing around the world about the threat Iran may pose to the region, and particularly Israel, if it develops a nuclear weapon.

McCain, who has been one of the most vocal critics of the administration’s approach to foreign policy, said he is making the case “all the time” against Obama, from questioning why America let NATO take the lead in Libya last spring to “attributing directly” the problems in Afghanistan to the president’s “continuous statements of early withdrawals.”

McCain, who officially has endorsed former Massachusetts Gov. Mitt Romney for the GOP presidential nomination, added, “And Mitt makes the case,” too.

Despite his serious concerns with America’s foreign policy approach in a volatile time for the world, McCain conceded that what is happening thousands of miles away might not be on the minds of voters as they head to the polls.

“I think it’s a very important issue, but the question is: Is it important to the American people who are still worried about jobs and the economy?” McCain said. “It’s a vitally important issue, but I understand when Arizonans, when nearly half their homes are still underwater, they want to hear the candidates talk about how to solve the housing crisis.”

Obama addressed growing concerns with Iran and the nation’s continued attempts to build its nuclear capability, as well as Israel’s response to it, in an interview with the Atlantic magazine that was published Friday. Obama also defended himself against charges from Republicans that he would not take military action against Iran in the face of nuclear threats.

“If people want to say about me that I have a profound preference for peace over war, that every time I order young men and women into a combat theater and then see the consequences on some of them, if they’re lucky enough to come back, that this weighs on me — I make no apologies for that,” Obama said. “These aren’t video games that we’re playing here.”

But he said Iran and Israel should know that he doesn’t “bluff” when it comes to the United States’ resolve to keep nuclear weapons out of the hands of Iranians. “When the United States says it is unacceptable for Iran to have a nuclear weapon, we mean what we say,” he said.

He also challenged Republicans on the charge that he has not been a strong leader, noting his decisiveness in going after bin Laden.

“It’s not an argument that the American people buy. They may have complaints about high unemployment still and that the recovery needs to move faster, but you don’t hear a lot of them arguing somehow that I hesitate to make decisions as commander in chief when necessary,” Obama said.

In fact, it’s not an argument many Republicans have been quick to make. Cornyn, for example, when discussing foreign policy, brought up the idea of “leadership” but used it to pivot to the economy, noting that Obama is “generally not able to [lead] in domestic policy.”