It's right to view the Tea Party's members and fellow travelers as fixated on domestic politics and policy. But it's wrong to reckon that they will fail to have a serious and invariably disruptive impact on future foreign policy. Indeed, their power is likely to grow, despite their defeats in October over the federal budget and the debt ceiling. Their sway will mount because they still face little effective opposition from within the Republican Party in most parts of the nation. And there is little doubt about the damage they can and will inflict: They will threaten what remains of the Republican Party's great tradition of internationalism and further strain the ability of any U.S. President to conduct diplomacy, to negotiate, and to compromise. To Tea Party members, these three staples of a successful foreign policy are akin to unilateral disarmament.
Republican and Democratic internationalists should not console themselves because of the apparent divisions among Tea Partiers over foreign policy—the seeming divide between unashamed isolationists like Rand Paul and unabashed hawks such as Ted Cruz. It would be wrong to bet on those differences marginalizing the movement's impact. More likely, the Tea Party's varying messages will fuse into a reborn and more potent form of hawkish isolationism.