The Best Foreign-Policy Approach for America Is... act on behalf of the American people. Other nations might benefit incidentally, but their welfare should be of concern to the U.S. only as their situation affects America.

Americans typically vote on economic issues. But they can’t escape the world. Foreign policy has a way of unexpectedly intruding in people’s lives. Unfortunately, Washington’s actions abroad affect the size and power of Washington at home. “War is the health of the state,” declared social critic Randolph Bourne. The more active America’s foreign policy, the more the United States has to spend on the military: the “defense” budget is the price of Washington’s foreign policy. American military personnel and contractors die. Enemies are created, some of whom become terrorists. A national security state develops. In the end, war is the biggest big government program.

Thus, Americans committed to limited government and individual liberty should support a foreign policy based on humility and restraint. There always will be arguments over details, but an imperial foreign policy like that followed by the United States today inevitably inflates, and indeed, requires, a Leviathan state.

Nor should anyone who understands government—libertarians, classical liberals, public choice economists, and general realists—believe the American state to be capable of competently fulfilling the more expansive foreign policy objectives commonly assigned to it. At times war is an unfortunate necessity, and government must rain down death and destruction on anyone seeking to harm America or Americans. Far more often, however, policymakers turn the military into just another government tool intended to achieve complicated ends that often aren’t even important, let alone vital. Attempts at so-called humanitarian intervention and nation-building, for instance, almost always turn out badly, even disastrously.

Yet domestic warrior wannabes often are not alone in promoting America’s warfare state. So do foreign classical liberals who campaign in their home countries for market-friendly policies, responsible spending practices, and limitations on state power. While these intellectuals and activists sometimes look a lot like U.S. Tea Party activists in promoting smaller governments, many of them expect the American state, or at least the Pentagon, to be large. Not just big, but big enough to defend their nations from all comers.

This sentiment has grown particularly pronounced with the rise of Russia’s Vladimir Putin. It is granted that the Russian president has unpleasant objectives that leave neighboring states feeling uncomfortable, to say the least. A number “liberals” (as Europeans typically call what Americans are more likely to term “libertarians”) in those countries believe it is America’s job to protect their nations, even, conceivably, if doing so would mean war. Some appear almost mystified when their ideological compatriots in the United States object. For an American classical liberal, confronting a nuclear-armed power over issues which the latter views as vital but which matter little to America would be foolish, even improper, a violation of the federal government’s responsibility for the “common defense” of this nation and its people.

Foreign policy, which ultimately controls the use of military force, ought to be uniquely national, practical, and circumstantial.

First, it makes no sense to speak of a transnational approach to international relations. The world’s people are organized in nation states. Individual countries might choose to submit some of their decisions to treaties or organizations, but do so based on an individual assessment that their citizens gain more than they lose from the process. Foreign policies of nations naturally will differ. Even transporting the same politicians from one country to another would yield different approaches to international affairs, since states’ interests vary.

Second, foreign policy is eminently practical. The broad objective is simple: advance the interests of one’s nation. Philosophical principles might affect the means used. For instance, all liberals should reject aggressive war. However, ideology cannot determine what actually will succeed in effecting a particular end in a particular situation. Ultimately, what matters most is what works. Equally important is learning what won’t advance one’s goals, or, would in fact, would actively impede them.

Third, foreign policy is circumstantial. That is, it depends on the particular facts. Thus, appropriate policy not only should vary based on such factors as location, neighbors, wealth, population, culture, and history, but also may change over time. Americans had one set of abilities, interests, and objectives during the Revolutionary War, but very different sets as Europe careened off into war twice last century and as the Cold War later concluded. U.S. foreign policy should look different each time.

Taking these factors into account, Washington should act on behalf of the American people. Other nations might benefit incidentally, but their welfare should be of concern to the United States only as their situation affects America. The fact that Moscow, for instance, is beating up Georgia or Ukraine matters in a geopolitical sense only insofar as those actions threaten the United States. And they don’t.