Is War Declining—and Why?


Credit: Curaphotography: Dreamstime

British philosopher Thomas Hobbes asserted in his 1651 book, Leviathan that "it is manifest that during the time men live without a common power to keep them all in awe, they are in that condition which is called war; and such a war as is of every man against every man." So in order to obtain peace and security people form a social contract in which they surrender some of their natural liberty to "a common power to keep them all in awe." And it fact, the modern anthropological literature does show that violence is endemic in pre-state societies. People living outside of states are in fact engaged in a war of every man against every man.

The good news is that the evidence for the declining trend in the mortality rate from violence continues to accumulate. The headline of this post is the title of a new article by University of Tel Aviv political scientist Azar Gat in the journal Peace Research. Gat's review of the recent literature finds:

…that claims a sharp decrease in fighting and violent mortality rate since prehistory and during recent times. It also inquires into the causes of this decrease. The article supports the view, firmly established over the past 15 years and unrecognized by only one of the books reviewed, that the first massive decline in violent mortality occurred with the emergence of the state-Leviathan. Hobbes was right, and Rousseau was wrong, about the great violence of the human state of nature. The rise of the state-Leviathan greatly reduced in-group violent mortality by establishing internal peace. Less recognized, it also decreased out-group war fatalities. Although state wars appear large in absolute terms, large states actually meant lower mobilization rates and reduced exposure of the civilian population to war. A second major step in the decline in the frequency and fatality of war has occurred over the last two centuries, including in recent decades. However, the exact periodization of, and the reasons for, the decline are a matter of dispute among the authors reviewed. Further, the two World Wars constitute a sharp divergence from the trend, which must be accounted for. The article surveys possible factors behind the decrease, such as industrialization and rocketing economic growth, commercial interdependence, the liberal-democratic peace, social attitude change, nuclear deterrence, and UN peacekeeping forces. It argues that contrary to the claim of some of the authors reviewed, war has not become more lethal and destructive over the past two centuries, and thus this factor cannot be the cause of war's decline. Rather, it is peace that has become more profitable.(emphasis added) At the same time, the specter of war continues to haunt the parts of the world less affected by many of the above developments, and the threat of unconventional terror is real and troubling.

In his new book, Human Capitalism, Cato Institute senior fellow Brink Lindsey notes:

Contrary to romantic fantasies about noble savages, the evidence now suggests that intergroup interaction in the prehistoric era was unremittingly violent. According to anthropologist Lawrence Keeley, about 0.5 percent of the population died every year from warfare. To put that modest-sounding figure in perspective, consider the fact that about one hundred million people died in the bloody wars of the twentieth century. Had the prehistoric mortality rate still prevailed, however, the death toll would have been two billion!

Although Lindsey's 100 million killed in the 20th century may be an undercount, even doubling it shows a considerable decline in the rate of violent deaths. The fact that you are less likely to die a violent death today than at any other time in human history and that violence has been declining for centuries was also reported by Harvard University psychologist Steven Pinker in his book. The Better Angels of Our Nature: Why Violence Has Declined. Go here to see my interview with Pinker.