BQ 1. Why no World War III?

The big questions of history

In 1900 David Hilbert, a German mathematician, compiled a list of important unsolved problems for his colleagues to investigate during the century to come. Hilbert was one of the biggest names in the profession, and his challenge elicited the best efforts of generations of mathematicians. Of the twenty-three problems he posed, several were subsequently solved, while others were shown to be unsolvable, which to mathematicians is an equally satisfactory outcome. Still others, while remaining neither solved nor proved unsolvable, inspired work that productively expanded the boundaries of mathematics.

In the spirit of Hilbert, in this and future installments I’ll propose a series of questions for historians to investigate. As in Hilbert’s case, the questions aren’t novel. They’ve engaged historians for years—or decades or centuries. And though historical questions don’t lend themselves to definitive answers the way mathematical questions often do, like Hilbert’s questions they might inspire investigations that will prove useful in their own right. In fact they already have.

To begin:

1. Why has there been no World War III?

I put this one first because it's the only one capable of being overtaken by events. A third world war could begin tomorrow.

But actually it's part of a larger question: Why do wars occur?

Potential answers to the original question can be extrapolated to the larger one. A common explanation for the absence of World War III is that nuclear weapons have made such a war too costly for the belligerents. It's not unreasonable to think that decisions for war include cost-benefit analyses. If the likely costs of a war outweigh the likely benefits, that war probably won't happen.

The problem with this explanation is that it's very difficult to test. Both the costs and benefits of a war that hasn't yet been fought are impossible to know. And in the case of decisions against war, it is almost tautological. A regime would be irresponsibly foolish to declare war while believing that it would lose more than it would gain.

To be sure, nuclear weapons make the potential costs of war far greater than in the past. The potential benefits have not risen commensurately. Hence war is less probable than before.

Yet not impossible. A regime might use tactical nuclear weapons not intending itself to escalate and not expecting its adversary to do so. Russia might employ nukes against Ukrainian troops, judging America wouldn't respond in kind. Vladimir Putin might think an American president would never risk New York to save Kyiv.

Or a regime might believe that its existence was threatened and that only nuclear weapons could save it. Israel has not acknowledged possessing nuclear weapons but it has let adversaries know that it would use its nukes if faced with destruction.

In both of these cases, a rational cost-benefit analysis could recommend the use of nuclear weapons. In the former, the cost is reduced by the supposition of non-retaliation. In the second, the benefit is increased by the necessity of saving the regime.

Beyond this is the possibility of irrational nuclear war. It’s not always easy to identify irrationality. What seems reasonable to me might seem crazy to you. But it is not infrequently supposed that if Germany had developed nuclear weapons during World War II, Hitler would have used them even if he had known they wouldn’t change the outcome of the war. He killed himself, so why not take down as many others as possible?

The reason for dwelling on the role of nuclear weapons in preventing World War III is that the different possible answers to the question point in different policy directions. If nukes were the main reason there has been no World War III, then prudent policy would be to keep them available and ready for use. On the other hand, if they were not the main reason, then they are a terrible accident waiting to happen, and prudence would dictate trying to rid the world of them.

What are other plausible explanations for no World War III? One might be the existence of trade ties. Maybe economic globalization has prevented World War III. Countries tend not to go to war with their best customers. American leaders, motivated by this belief, deliberately pursued economic integration after 1945. They godfathered what became the European Union by premising Marshall Plan aid on cooperation among the recipients. Working through the General Agreement on Tariffs and Trade, the forerunner of the World Trade Organization, they negotiated serial reductions in tariffs toward the goal of free trade. Besides making former enemies think of each other as partners, these efforts promoted broad-gauged prosperity, which by itself is typically a deterrent to war.

The problem with this explanation is that similar trends failed to prevent World War I. The international gold standard promoted by Britain fostered the first age of globalization in the late 19th and early 20th centuries. European leaders thought they had solved the problem of war. Workers too seemed determinedly pacifistic. Many came to think they had more in common with fellow workers in other countries than with the bosses in their own. Some went so far as to vow not to fight if their governments declared war. But these antiwar intentions evaporated in just a few months in the summer of 1914.

Another possibility is that humans simply aren't as belligerent as we used to be. Maybe we learned something and decided that enough war was enough. It's true that Europeans were saying essentially the same thing to themselves during the long period of peace between 1815 and 1914, and then engaged in the two most horrific wars in history. But people sometimes do learn from their mistakes, and maybe our species just doesn't have another world war in it. We used to be cannibals but don't eat each other anymore. We used to engage in human sacrifice and dispensed with that. So why not forgo war—at least general war?

What this all adds up to is that we don't know why there hasn't been a third world war. Which is why the question is on this list. And this question came first not simply because events might render it moot, but because if we can figure out the answer, we might be able to change the tense of the question from “hasn’t been” to “wasn’t.” We figured out how to prevent epidemics of smallpox and some other diseases. We've done a pretty good job of consigning famine to history. There's no inherent reason we shouldn't do the same to war.

So, historians: Get to it!