Schelling’s intellectual contribution will receive a lot of discussion over the coming days and weeks. He was one of the most important thinkers about game theory, an approach to modeling strategic interactions that has remade entire fields of study in the social sciences. Yet his work is anything but technically forbidding. He was a beautifully clear and precise writer. His three major books, “The Strategy of Conflict,” “Arms and Influence,” and “Micromotives and Macrobehavior” can be read by anyone with even a minimal exposure to social science thinking. Of these three, “The Strategy of Conflict” is a classic — a book that ought be read by everyone. Its ideas are not only relevant to international politics but to everyday life, the study of criminal behavior, and multitudes of other topics.
Schelling’s key arguments explain how communication happens. If we want to get others to do what we want, we need to communicate with them. Sometimes, when we do not have conflicting interests, we can coordinate on a shared solution, even if we are not able to talk with each other very well. If we want to meet in New York, but are not able to communicate with each other about the place and time, we can draw on our common knowledge to figure out a plausible place and time to meet up (perhaps Grand Central Terminal at midday). This is because some possible places and times to meet are salient — that is, our shared knowledge highlights them as ‘obvious’ solutions to the problem of coordinating on place and time. This simple insight turns out to have profound consequences for the study of cooperation.
However, sometimes we may have interests that conflict with each other, or even be enemies. Here too, communication can play a key role, but it is most likely to be effective if it is credible. For example, I might threaten to punish you if you do something that I don’t want you to do. However, punishing you is likely to be costly. This means that if you go ahead and do whatever it is that I don’t want you to do, I may then decide that it isn’t worth punishing you after all. And this also means that you (if you are farsighted) might look ahead into the future, figure that I am not going to punish you and do whatever you want to. In other words, my threat isn’t credible to you. To make my threats credible, I will have to bind myself somehow — constrain myself in ways that will make me deliver on the threat even if it is painful and costly for me.
Schelling used these basic insights to radically change the ways in which we think about conflict. When he started writing — at the beginning of the Cold War — the U.S. and the USSR didn’t have any very good way of communicating credibly with each other. This meant that the risk of disaster was very high. During the Cuban missile crisis, the U.S. and USSR nearly bluffed each other into a full scale nuclear war. Schelling’s contribution was to show how the two sides could think systematically about coordinating (where they had common interests) and deterring each other from unwanted actions (where they did not). This arguably gave rise to a much more stable world — the world of the Cold War — where both sides struggled with each other for dominance, but tacitly agreed on some of the rules of the game, and didn’t try to push each other too far. The Cold War was organized around deterrence, and deterrence mostly rested on Schelling’s ideas about credible threats
This logic had some remarkably coldblooded consequences, which Schelling described with a certain gusto. The U.S. stationed a small garrison in Berlin, which was embedded deep in East German territory, and indefensible against any serious attack. As Schelling described it, these soldiers’ job was not to defend the city but to die if it were attacked. This would then trigger a large scale U.S. response, since no U.S. president could tolerate the USSR killing American soldiers and not retaliate. Hence, by the logic of credible threats, the USSR would not attack Berlin, since it knew that the U.S. would have to punish it harshly, since it had effectively bound itself to deliver on the implied threat. Similarly, Schelling argued that the loss of thousands of American soldiers in the Korean War was a small price to pay if it preserved the U.S. reputation for resolve.
In Schelling’s framework, conflict was a kind of language, in which the words, sentences and paragraphs were composed of soldiers, nuclear missiles, and the deaths of myriad civilians. In a limited nuclear conflagration, the U.S. should target some USSR cities and not others, in order to convey messages to the other side about what its intentions were, and what it could and would do if it were truly provoked. This way of thinking was parodied in the movie “Dr. Strangelove” — yet it also helped prevent nuclear catastrophe over a period of decades. The Cold War was a vast intellectual construct in which threats that were never delivered on, and things that never happened had enormous consequence for what did occur. Threats that are truly credible never have to be delivered on. Our understanding of how a Cold War could provide stability is owed to Schelling.
I never met Schelling, although I greatly admired his work. He lectured my kids’ Cub Scout troop a year or two before they joined up — he was a proud Eagle Scout. Schelling is far less well-known to the public than other scholars-turned-international-affairs-intellectuals such as Henry Kissinger, yet his legacy is inversely vaster and more profound.