This range of answers is fairly insipid (two years as missionary in France?) until you realize that the Senators had nothing else to say; Romney really doesn't have foreign policy experience.
Alabama Senator Jeff Sessions did his best, claiming that Romney "seems to instinctively understand foreign policy and, of course, he was commander of the national guard." Arizona Senator John McCain declared of Mitt Romney, "He's got all the right instincts...To me, he's Reaganesque."
Good instincts? Really? Does Sessions honestly think Gov. Romney had any meaningful interaction as commander of the Massachusetts national guard during his one term? And have Sessions or McCain forgotten how incompetent Romney looked in Great Britain and Israel? The man the media in America and Europe are calling a wimp McCain thinks is Reaganesque? Ferchristsake, Senator, give your brain a chance. Whatever else you may like about Romney, his political instincts should not be one of them.
McCain slammed Romney in 2008 precisely because Mitt had no foreign policy experience. McCain's claim, as presidential candidate, was that he, McCain, had a more extensive background in foreign policy generally as well as in national defense, which is where the commander-in-chief issue becomes especially relevant.
It was a fair point at the time, Senator, but now you think Romney has "all the right instincts"?
Recall how Obama was also slammed for this very reason; he also had thin foreign policy experience. And Republicans lined up to tell voters how terribly important foreign policy experience is and how dangerous it would be to elect that inexperienced senator from Illinois. Now that the shoe is on the other foot, Republican Senator Ron Johnson said, "Listen, you know what his experience is, and there are very few people who run for president who have all kinds of foreign-policy experience."
Obama also lived overseas, as well as Hawaii, where he experienced a diverse upbringing. That, of course, has often been used against him. Too exotic, you see. Not reliably American, which is code for not a white guy, not from the heartland.
The same people who attacked John Kerry in 2004 because he seemed "too French," and because he said he liked French cuisine are the same people are now saying Romney's missionary work in France, where he went to avoid military service in Vietnam, should be viewed as a foreign policy plus?
The same Republican senators who say foreign policy experience is very important, and then admit Romney has very little of it are compelled to ignore the obvious; the only candidate who has a great deal of foreign policy experience is President Obama, who enjoys the inherent advantage of every incumbent. Whatever arguments that could have been made against Senator Obama in 2008 about his limited experience are out the door and completely irrelevant in 2012.
Republicans are not going to make much of the presidential-executive-foreign policy-commander-in-chief experience factor now because only President Obama meets their criteria.