# When Will We Have Another World War? History Says Soon, According to New Mathematics Study

Lately, people have been understandably worried that we might be coming close to another world war. But although more than 95 wars have happened in the last 200 years, our bloodlust has actually slowed since World War II. Not counting wars fought through proxies (as in Korea and Vietnam), peace among major geopolitical superpowers has been unusually long-lasting.

But will the peace continue? That’s what University of Colorado researcher Aaron Clauset hoped he might find out—using math. Clauset put 200 years of data about war through a statistical analysis and came to the conclusion that a battle the size of World War II could happen again soon. His analysis was published in Science Advances on February 21. Clauset spoke to Newsweek about his findings.

This interview has been edited and condensed.

How does World War II compare to other wars included in your study?

World War II was not an outlier relative to the historical record.

What is the significance of that finding?

It’s plausible that a global, geopolitical dynamic is producing all of these wars. That means, if we look at the next 100 years, we can calculate the [likelihood] that we might see an event that’s that large or larger. This is just a mathematical calculation. It’s not a prediction. It’s not saying that it will happen.

Do we have any idea what that war might look like?

The mathematics doesn’t take into account who might fight the battle, why it might start in the first place, what kind of weapons might be used, or where in the world it might be. It doesn’t say that it’s going to involve the U.S. at all, for example.

And there’s no guarantee that the future will actually be like the past. If mechanisms that people have identified as reducing the risk of war are indeed having an impact, then the risk of a large war might be lower than the statistical model might predict.

Why did you conclude that a war that will kill more than a billion people may happen some time in the next 1,300 years or so?

The hazard rate [the likelihood of something happening] of having a civilization-ending wars is small in an individual lifetime. But thinking about the lifetime of a civilization, it’s not very small. One thousand years might not be a long time for a long-running, technological civilization.

But isn’t the time in which we live different from the era of World War II? And if so, doesn't that change the likelihood of a large war such as that?

The conclusion, based on the data, is that we cannot tell that things have changed. The data do not allow us to claim that the post-war period is any different from the period before World War II.

But if there’s been this long peace, doesn’t this mean we might be less violent as a society?

There’s a broader debate that this paper fits into. One side espouses the notion of liberalism, this idea that things are getting better and more peaceful. The most outspoken proponent of this side right now is [Harvard University cognitive scientist and author] Steven Pinker.

People who espouse liberalism point to specific processes that we know have reduced the risk of war—things like the spread of democracies and peacetime alliances, increasing economic ties and so on. The other side is the realism side, which argues that the hazard rate of war is not changing over time.