Among conservatism’s foreign policy elite, Rubio’s worldview commands more support. But in the grass roots, it’s a different story. A recent Pew poll found that the share of conservative Republicans agreeing that the U.S. should “pay less attention to problems overseas” has risen from 36 percent in 2004 to 55 percent today. In the debate over Libya, Tea Party icons like Michele Bachmann and Sarah Palin have sounded more like Paul than Rubio, and a large group of House Republican backbenchers recently voted for a resolution that would have brought the intervention screeching to a halt.
This is all true, but it tells you very little about the foreign policy of the next Republican president, because it ignores partisanship. Republicans have a hawkish faction that supports every military intervention, and Democrats have a liberal faction that opposes every military intervention. But large numbers of both parties make their decision about any particular intervention based on whether they trust the president -- which means whether he's in their party or not.
It's true that some Republicans are sounding anti-interventionist notes now. George W. Bush himself ran in 2000 as an anti-interventionist, attacking the Clinton administration for its nation-building and promising a more "humble" foreign policy. The Republican fear of reckless American intervention disappeared as soon as Clinton did, and it will disappear again as soon as a Republican takes the oath of office.
This is, to be sure, a bipartisan phenomenon. Barack Obama and many other Democrats sounded far more anti-war while running for office than Obama has governed. The point is that campaign rhetoric about foreign policy, while interesting in its own right, does not provide an accurate guide to how a party would contact foreign policy from the White House.