with the bird’s-eye view of the 20th century in figure 6–1. The viewing was arranged by Lacina, Gleditsch, and Russett, who retrofitted numbers from the Correlates of War Project from 1900 to 1945 to the PRIO dataset from 1946 to 2005, and divided the numbers by the size of the world’s population, to yield an individual’s risk of dying in battle over the century.
The graph reminds us of the freakish destructiveness of the two world wars. They were not steps on a staircase, or swings of a pendulum, but massive spikes poking through a bumpy lowland. The drop-off in the rate of battle deaths after the early 1940s (peaking at 300 per 100,000 people per year) has been precipitous; the world has seen nothing close to that level since.
Eagle-eyed readers will spot a decline within the decline, from some small peaks in the immediate postwar decade to the low-lying flats of today. Let’s zoom in on this trend in figure 6–2, while also subdividing the battle deaths according to the type of war that caused them.
FIGURE 6–1. Rate of battle deaths in state-based armed conflicts, 1900–2005
Source: Graph from Russett, 2008, based on Lacina, Gleditsch, & Russett, 2006.
FIGURE 6–2. Rate of battle deaths in state-based armed conflicts, 1946–2008
Civilian and military battle deaths in state-based armed conflicts, divided by world population. Sources: UCDP/PRIO Armed Conflict Dataset; see Human Security Report Project, 2007, based on data from Lacina & Gleditsch, 2005, updated in 2010 by Tara Cooper. “Best” estimate used when available; otherwise the geometric mean of the “High” and “Low” estimates is used. World population figures from U.S. Census Bureau, 2010c. Population data for 1946–49 were taken from McEvedy & Jones, 1978, and multiplied by 1.01 to make them commensurable with the rest.
This is an area graph, in which the thickness of each layer represents the rate of battle deaths for a particular kind of state-based conflict, and the height of the stack of layers represents the rate for all the conflicts combined. First take a moment to behold the overall shape of the trajectory. Even after we have lopped off the massive ski-jump from World War II, no one could miss another steep falloff in the rate of getting killed in battle that has taken place over the past sixty years, with a paper-thin laminate for the first decade of the 21st century at the end. This period, even with thirty-one ongoing conflicts in that mid-decade (including Iraq, Afghanistan, Chad, Sri Lanka, and Sudan), enjoyed an astoundingly low rate of battle deaths: around 0.5 per 100,000 per year, falling below the homicide rate of even the world’s most peaceable societies.20 The figures, granted, are lowballs, since they include only reported battle deaths, but that is true for the entire time series. And even if we were to multiply the recent figures by five, they would sit well below the world’s overall homicide rate of 8.8 per 100,000 per year.21 In absolute numbers, annual battle deaths have fallen by more than 90 percent, from around half a million per year in the late 1940s to around thirty thousand a year in the early 2000s. So believe it or not, from a global, historical, and quantitative perspective, the dream of the 1960s folk songs has come true: the world has (almost) put an end to war.
Let’s take our jaws off the table and look more closely at what happened category by category. We can start with the pale patch at the bottom left, which represents a kind of war that has vanished off the face of the earth: the extrastate or colonial war. Wars in which a great power tried to hang on to a colony could be extremely destructive, such as France’s attempts to retain Vietnam between 1946 and 1954 (375,000 battle deaths) and Algeria between 1954 and 1962 (182,500 battle deaths).22 After what has been called “the greatest transfer of power in world history,” this kind of war no longer exists.
Now look at the black layer, for wars between states. It is bunched up in three large patches, each thinner than its predecessor: one which includes the Korean War from 1950 to 1953 (a million battle deaths spread over four years), one which includes the Vietnam War from 1962 to 1975 (1.6 million battle deaths spread over fourteen years), and one which includes the Iran-Iraq War (645,000 battle deaths spread over nine years).23 Since the end of the Cold War, there have been only two significant interstate wars: the first Gulf