Peter Beinart, senior political writer for The Daily Beast, is associate professor of journalism and political science at City University of New York and a senior fellow at the New America Foundation. His new book, The Icarus Syndrome: A History of American Hubris, is now available from HarperCollins. Follow him on Twitter and Facebook.

Every four years, Republican president candidates promise to emulate Ronald Reagan. This year, surprisingly, they’re actually doing it.

I’m referring to their comments on Afghanistan. At last week’s GOP debate, Mitt Romney shocked neoconservatives by declaring that America "shouldn't go off and try and fight a war of independence for another nation." Jon Huntsman has gone further, declaring that “the very expensive boots on the ground may be something that is not critical for our national-security needs, nor is it something we can afford [at] this point in our economic history.” Even Newt Gingrich ventured that "We should say to the generals, ‘We would like to figure out [how] to get out as rapid [sic] as possible with the safety of the troops involved.’” So far, at least, not one major Republican hopeful is arguing that the U.S. must do whatever it takes to win the war that America launched after the 9/11 attacks.

The Republican foreign-policy establishment is appalled. Danielle Pletka, head of foreign policy at the American Enterprise Institute, has called Romney a “weather vane.” But if being a weather vane means trying to avoid wars that America can’t afford and the American people won’t sustain, the Republican presidential field has a lot more in common with Ronald Reagan than do the uber-hawks that form the GOP’s permanent foreign-policy class.

The dirty little secret of Reagan’s foreign policy is that he was extremely reluctant to send U.S. troops into harm’s way—more reluctant, in fact, than every president who has followed him...