A look at how others stack up:
—Mitt Romney, the former Massachusetts governor and venture capitalist, traveled to more than 30 countries as a businessman, Olympics official and politician.
Recently, he has said that Obama "has been unable to construct a foreign policy" because of his "fundamental disbelief in American exceptionalism." America is seen as weak, Romney said, because "we're following the French into Libya" to support those rebelling against Moammar Gadhafi.
—Tim Pawlenty made trade missions and troop visits as Minnesota governor to Iraq, India, China, Brazil, Chile, Afghanistan, Bosnia, Germany, Israel, Kosovo, Kuwait, Poland, Spain and other places.
He was among the first to call for a no-fly zone to protect Libya's rebels from Gadhafi's forces. And he criticized Obama for taking almost two more weeks to take that step.
—Newt Gingrich, the former House speaker best known for his interest in domestic issues such as tax policy and health care, sits on the Council on Foreign Relations' terrorism task force, and teaches at the National Defense University.
He calls for a muscular approach to combating terrorism. But he was widely mocked recently for an about-face on Libyan policy. First he said he would "exercise a no-fly zone" and get rid of Gadhafi. Two weeks later, he said: "I would not have intervened. ... I would not have used American and European forces."
—Mike Huckabee, the former Arkansas governor and 2008 Iowa caucus winner, has traveled extensively, including numerous trips to Israel.
He was criticized in 2007 for saying that, as president, he would strike at terrorists inside Pakistan with or without permission from that country's leaders. It looks rather prescient in light of this week's events; Obama didn't notify Pakistan before authorizing the raid that killed bin Laden.
—Rick Santorum, the former Pennsylvania senator, spent much of his Capitol Hill career serving on committees covering agriculture, banking, housing and urban affairs, and other domestic matters.
Lately, he has accused Obama of "dithering" in Libya and creating a "morass" because he let the international community take the lead in aiding Gadhafi's opponents.
—Sarah Palin, the 2008 vice presidential nominee and former Alaska governor, was widely ridiculed for suggesting she had foreign policy credentials because "you can actually see Russia from land here in Alaska."
She has worked to expand her foreign experience, including trips to Iraq, India and Israel.
- See photos of reactions to Osama bin Laden's death.
- See a slide show of six potential terrorist targets.
- See photos of U.S. troops in Afghanistan.
- Get the latest Washington news delivered to your inbox.