The Realist Guide to World Peace

It's the holiday season, that brief period each year when we are encouraged to think about peace. Warring armies sometimes declare cease-fires at this time, and around the world different communities of faith are told that pursuing and preserving peace is a sacred duty. If we are fortunate, most of us will spend some part of the next few days enjoying the company of friends and family and trying to put humanity’s crueler instincts to the side, at least for the moment.

Let's be honest: 2022 was not a good year for peace. In addition to a brutal and senseless war in Ukraine—a war that shows no signs of ending and could still get much worse—violent conflicts are still underway in Yemen, Myanmar, Nigeria, Ethiopia, Syria, and many other places. Although U.S. President Joe Biden and Chinese President Xi Jinping managed a fairly cordial meeting at the G-20 summit in Bali in November, the two most powerful countries in the world remain divided on a host of important issues. Given the state of the world and the United States' desire to remain the leading global power, it should surprise no one that the Senate just voted an 8 percent increase in the U.S. defense budget. Even formerly pacifist-leaning countries such as Germany and Japan took dramatic steps to rearm during 2022.

For a realist like me, these developments aren't surprising. Realism's central lesson is that in a world of independent countries without a central authority, the ever-present possibility of war casts a shadow over much of what states do. Because warfare is inherently destructive and often uncertain, realists tend to be wary of idealistic crusades and mindful of the danger of threatening what others regard—justifiably or not—as vital interests. Instead, realists of all stripes emphasize the tragic features of a world in which leaders are easily misled by poor information or their own delusions, where even noble aims can produce regrettable results.

But neither realists nor their critics can simply throw up their hands and declare there is nothing to be done about the possibility of serious conflict. War between and within states may be a constant danger, but the real challenge is to devise and implement policies that will minimize the risks of new wars and help bring existing ones to an end. Because the benefits of peace and the costs and risks of war have never been greater, this imperative may be more urgent today than at any time in human history.

First, the benefits. Many people believe economic interdependence promotes peace both between and within countries, an idea that Russia's invasion of Ukraine casts doubt upon. The reverse is more likely to be true: Peace makes interdependence more feasible and allows us to enjoy the benefits of economic exchange at lower risk. When the danger of war declines, investors can safely send capital to other countries; governments can worry less about whether their trading partners are gaining a bit more from the exchange; states can welcome foreign visitors and students without concern that rivals will be acquiring knowledge that might be used to harm them; elaborate supply chains are less risky; and everyone can pursue joint gains instead of constantly striving for relative advantage. The absence of serious rivalry among the major powers facilitated the recent era of globalization, producing enormous benefits for mankind despite its deficiencies. And when war is off the table, societies can be more open to exchanging ideas and lessons from cultures that are different from their own....