Johnson, a former Republican governor of New Mexico, believes that so-called defense spending should be used for defense, that the United States "should resort to military action as the last option and only as provided in the Constitution" and that our foreign policy should be "reoriented toward the protection of U.S. citizens and interests." Obama and Romney, by contrast, believe "it is the responsibility of our president to use America's great power to shape history," as Romney put it in a recent speech.
During last week's vice presidential debate, Romney's running mate, Paul Ryan, struggled mightily to distinguish the two major parties' foreign policies. He was reduced to squabbling with Vice President Joe Biden about how often Obama meets with Israeli Prime Minister Benjamin Netanyahu and faulting the administration (over and over again) for describing Syrian autocrat Bashar Assad as a "reformer."
Ryan's main message was that Romney would do basically what Obama is doing but with more "credibility." It was clear that on all the major foreign policy issues Ryan and Biden discussed -- including Iran, Iraq, Afghanistan, Libya and Syria -- Obama and Romney have essentially the same positions.
In a debate limited to Obama and Romney, you will not hear anyone question, as Johnson does, whether frustrating Iran's nuclear ambitions is worth launching yet another war in the Middle East. You will not hear anyone wonder, as Johnson does, whether occupying Afghanistan for 13 years was the only way to "make sure that the Taliban does not come back in and give al-Qaida a safe haven," which is how Ryan described the aim of the longest war in American history.
Biden did allow that as of next year "it is the responsibility of the Afghans to take care of their own security." What about Europe, Japan and South Korea? That's the sort of question Johnson asks but Obama and Romney never will.
Another Johnson theme neglected by the two major parties: The Constitution requires the president to obtain congressional approval before starting a war. Although Obama once thought that principle was pretty important, he changed his mind after he was elected president, unilaterally intervening in Libya's civil war. Romney main complaints at the time were that Obama did not do so sooner and that he rashly ruled out the use of ground forces.