The case for realism and restraint.

• Author: Ruger, Will

What role should the United States play in the world? When we ask that question, we are talking about foreign policy: the sum of our defense policy, trade policy, and diplomatic relations with other countries.

The answer: The U.S. should adopt a foreign policy that is both consistent with a free society and aimed at securing America's interests in the world--in other words, libertarian realism. The goal must be to provide security efficiently without sacrificing other important goals that Americans hold in common.

An important caveat up front: There is no universal, one-size-fits-all foreign policy for the ages. A single, comprehensive policy cannot be applied uniformly to any state at any period in history. Geography, institutional constraints, technology, history, and strategic context will always shape how we conduct foreign policy. So the U.S. today might require a very different approach than it needed during, say, the early Cold War or the first years of the republic.

But today, American defense policy should be characterized by strategic restraint; its economic policy must be one of free trade, and its diplomacy ought to be focused on articulating--but not aggressively imposing--liberal values and the benefits of free markets.

Ends and means in politics and war are intimately connected. The primary goal of the state should be to protect the territorial integrity of the United States and the property rights--broadly understood, including throughout the global commons--of the people residing within it. The state is also tasked with securing the conditions that allow for a free people to flourish in America. These elements combine to form the national interest.

The state's role is properly limited to serving these interests rather than meeting the needs of outsiders or of the state itself. However, a libertarian realist foreign policy will have positive benefits for Americans and people of other countries beyond achieving these fairly limited ends.

Realism is important to this schema because, in order to secure our interests properly, we need to understand the world as it is, not as we would like it to be. Realists recognize there are important limiting and complicating factors in politics, just as there are in economics. We can no more wish away the constraints that an anarchic world, the balance of power, and geography impose on statesmen than we can disappear the laws of supply and demand or comparative advantage. We need to understand and adapt to what realism tells us about the laws of international relations.

For example, we might wish we...