130+ years of steadily increasing war

U. WARWICK (UK) — Economic growth and a proliferation of new countries have kept the frequency of war at a steady incline for the past century.

A new study shows that the number of conflicts between pairs of states rose steadily from 6 per year on average between 1870 and 1913 to 17 per year in the period of the two World Wars, 31 per year in the Cold War, and 36 per year in the 1990s.

“The number of conflicts has been rising on a stable trend,” says Mark Harrison, professor of economics at the University of Warwick. “Because of two world wars, the pattern is obviously disturbed between 1914 and 1945 but remarkably, after 1945 the frequency of wars resumed its upward course on pretty much the same path as before 1913.”

One of the key drivers is the number of countries, which has risen dramatically—from 47 in 1870 to 187 in 2001.

“More pairs of countries have clashed because there have been more pairs. This is not reassuring: it shows that there is a close connection between wars and the creation of states and new borders,” Harrison says.

“No matter how you divide it, we have only one planet. Our planet has already seen two world wars. As that experience suggests, you can never be quite sure what little conflicts will not suddenly snowball into much wider, more deadly struggles.”

Pairwise conflicts, defined as the number of pairs of countries in conflict, has been rising since 1870 and is wide-reaching, including full-scale shooting wars and uses of military force to displays of force such as sending warships and closing borders.

The study, published in the Economic History Review, doesn’t measure the intensity of violence, but does capture the readiness of governments to settle disputes by force. Civil wars are not included in the study.

Not just America’s wars

Wars since 1945 are not just  “America’s wars,” Harrison says. Removing “America’s wars” altogether from the data, makes no difference: the rising trend is still there.

Perhaps surprisingly, while larger countries (defined by GDP) have tended to make more frequent military interventions, there is no increase in this tendency over the 130 years of the study, a statistic that holds true for richer countries as well.

In other words, the readiness to embark on military adventures is scattered fairly uniformly across the global income distribution.

This is puzzling, the researchers say, because conventional thinking says political leaders of richer, more democratic countries have fewer incentives to make war and are more constrained from doing so.

“We do not think these ideas are wrong, but they are incomplete,” Harrison says. “Without being certain of the answer, we think political scientists have focused too much on preferences for war (the “demand side”) and not enough on capabilities (the “supply side”).

Economic growth has made destructive power cheaper, not just absolutely cheaper but cheaper relative to civilian goods. Also, the key to modern states’ acquisition of destructive power was the ability to tax and borrow more than ever before, and the growth of fiscal capacity was hugely assisted by the rise of democracy. Finally, war is disruptive of trade, but those countries that succeeded in maintaining external trading links in wartime could wage war more effectively.

Capabilities may be the missing factor in the story of the rising frequency of wars. The very things that should make politicians less likely to want war—productivity, growth, democracy, and trading opportunities—have also made war cheaper, Harrison says.

“We are making war more frequently, not because we want to, but because we can.”

Researchers from Humboldt University contributed to the study.

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