I began to examine trends in warfare while writing The Better Angels of Our Nature, I quickly realized that without a
fixed yardstick you can demonstrate any trend you want. If you wish to paint a historical
period as violent, just include killings of all kinds, lump together deaths on the
battlefield with indirect deaths linked to famines and epidemics, and accept the
highest estimates that have been bruited about. Conversely, if you want to portray
a period as peaceful, restrict yourself to declared wars between governments,
count only the battlefield deaths, and be stringent about which estimates you
is only one way to elevate a discussion of war trends above the level of a barroom
argument, and that is to consult quantitative datasets assembled by disinterested
scholars who define what they count as a "war," stick to one criterion for
which deaths to tally, and exhaustively list all wars known to have taken place
during a set interval.
of these datasets are available, such as those of the Human Security Report
Project (HSRP). Most of the scholars who have examined them agree that the
decades since 1945 have seen a decline in wars among great powers and developed
states (what I call the Long Peace), and the decades since the end of the Cold
War have seen a decline in deaths from wars of all kinds (the New Peace). Disagreement
persists, to be sure, about the causes of the declines and how long they will
Arquilla's Dec. 2 article "The Big Kill," which claims
that war is on the increase, is a good illustration of the pitfalls of cherry-picking
conflicts, mashing up categories, and credulously selecting extreme estimates when
they help an argument along.
explain away the decline in deaths on the battlefield, Arquilla recycles the urban
legend that the proportion of war deaths suffered by noncombatants has risen from
10 percent during World War I to 90 percent in the wars of today. But this
factoid has been debunked by three political scientists (Andrew Mack, Joshua
Goldstein, and Adam Roberts), who each discovered that it compares battle
deaths in one era with battle deaths, indirect deaths, injuries, and refugees
then tries to make the decline go away with a different tactic: he claims it is
"skewed" by population growth since 1940. But this defies the mathematical principle
that a tendency can be estimated only by dividing the number of occurrences of
an event by the number of opportunities for it to occur; it's like choosing to
have surgery at a small hospital with a high complication rate rather than at a
large hospital with a low rate because the larger hospital has a greater
absolute number of complications. A tripling of the world population since 1940
means that there are three times as many people who can start wars and three
times as many people who can be killed in them. Even if the number of war
deaths had been constant over that interval, it would indicate a sharp decline
in the likelihood that a person will be killed in a war. In any case the absolute
number has not remained constant. It plunged from 224,000 a year in the 1950s
to 85,000 a year in the 1990s and 31,000 a year in the 2000s, so it doesn't even
matter whether you look at rates or absolute numbers.
decline is apparent even if one totals up the sheer number of armed conflicts in
the HSRP dataset, ignoring their annual death tolls (which can be as low as 25):
the count fell from 53 in 1991 to 30 in 2010, the most recent year available. Arquilla
points out that the 1991 peak represents an increase from the 1950s, but that
is consistent with the New Peace, which refers to a worldwide decline in all
kinds of war after the Cold War ended (as opposed to the post-World
War II decline of wars among great powers and developed states).
turns to what he calls "big-kill" wars, those that led to a million deaths, and
claims they have doubled every half-century since 1800. This trend, too, is being
measured with a rubber ruler. For the 20th century, Arquilla includes both wars
and genocides (such as those of Stalin and Pol Pot); for the 19th, he includes only
wars, omitting the massive death tolls associated with colonial wars, the Atlantic
and Mideast slave trades, the man-made famines in British India, and the
depredations in the Congo Free State. For that matter, his list of pure wars is
selective, omitting Shaka Zulu, the Panthay Rebellion, and the Mahdi revolt,
all with death tolls which exceed a million if one includes indirect deaths, as
Arquilla does for his 20th century. Indeed, for the second half of the 20th
century, Arquilla cites nonstandard highball estimates for the Rwandan genocide
and the Mozambique civil war, waffles between absolute and relative death
counts, and tries to sneak in near-misses (such as the Iran-Iraq war), none of
which he does for the earlier periods.
casual attitude toward data extends to quotations. Arquilla has me writing that
the past 70 years have seen "no spikes, just a couple of ‘blips." In fact, I do
refer to "spikes" during this period, while the word "blip" appears nowhere in
Steven Pinker, the author of The Better
Angels of Our Nature, is Harvard College Professor and Johnstone Family Professor
in the Department of Psychology at Harvard University.
Next: Andrew Mack and Sebastian Merz of the Human Security Research Project also respond.
By Andrew Mack and Sebastian
One of the most enduring myths about
the last hundred years of warfare is that, as John Arquilla's recent article puts it, "the deaths of noncombatants due to war has risen,
steadily and very dramatically." No compelling evidence has ever been produced
to affirm this assertion.
This is not surprising. There is none.
A careful review of the available data
on the deadliness of 20th century conflicts by Uppsala University's Margareta
Sollenberg found that there was no clear trend over time in the ratio of
civilian-to-military deaths in warfare -- let
alone the century-long increase from 10 percent to 90 percent that Arquilla and
many others claim has occurred.
In most wars about half the fatalities are
is variation in the ratio, of course, but no evidence that civilian deaths have
been inexorably increasing relative to combatant deaths over the past 100
Arquilla points to the war in the Democratic
Republic of the Congo as an example of what he and many others believe to have
been rising civilian death tolls in recent wars. Ninety percent of the
victims, he notes,
non-combatants. But these are not
civilians killed -- intentionally or otherwise -- as
a result of wartime violence.
overwhelming majority of these "indirect deaths" are individuals who are assumed to have died as a result of
war-exacerbated disease and malnutrition.
Arquilla is referring here to the much-cited survey
research undertaken by the International Rescue Committee (IRC), which found
that some 5.4 million individuals perished in Congo between 1998 and 2007.
These were individuals who would not have died had there been no war.
But the IRC's findings were seriously flawed in a
number of ways. Most importantly, two other surveys, the most recent by UNICEF,
found that nationwide mortality rates in the DRC were approximately half those reported in the IRC's
both the UNICEF survey and the earlier survey by the "gold standard" DHS
organization show a slow decline in
mortality rates prior to and throughout the war. The
IRC shows a huge increase in mortality after the war starts in 1998.
If the IRC is right, then the findings of two of the
world's major survey organizations must both be wrong.
This isn't the only problem with Arquilla's use of
the Congo death toll to help make his case. Reported death tolls in the other
"big kill" wars of the last 60 years don't normally include "indirect" deaths
caused by war-exacerbated disease and malnutrition. If they did, the toll for
the Korean War would likely be some 5-6 million greater than the estimates of
direct combat-related deaths
estimated at between 1.5 and
Critics may seize on such figures to argue that they
demonstrate that war is deadlier than "optimists" like Steven Pinker and the
Human Security Report Project suggest. They would be wrong to do so. While it
is true that the best estimates of battle deaths from armed conflict tend to be
conservative, the critical issue here is not absolute numbers, but trends -- whether
or not wars are becoming more or less deadly.
While no one doubts that "indirect" war death tolls
can exceed those of violent battle-related deaths -- sometimes substantially -- the
evidence suggests that, over recent decades, "indirect" death tolls have likely
declined to an even greater degree than violent deaths related to
First, today's wars are not only much less deadly in
terms of battle-related deaths, they also tend to be highly localized, with less than
20 percent of the national territory on average being directly affected by
Second, peacetime health interventions -- notably
the immunization programs that have covered greater and greater percentages of
national populations over the past three decades -- save lives in wartime.
Third, since the end of the Cold War there has been
a huge increase in funding for humanitarian assistance to war-affected
In both the latter cases, countless
thousands of individuals have survived who would likely have died in previous
when there were far fewer health interventions and much less humanitarian
During the past two decades, international efforts
to prevent wars and stop those that couldn't be prevented have increased
dramatically. If wars are increasing in number and deadliness as Arquilla
argues, these efforts will have been
best -- futile.
This is why getting it right about war trends
The evidence as we read it clearly indicates that
major wars are becoming less deadly and less frequent. And this -- and
other evidence -- suggests
that the large upsurge in
peacekeeping and peace-building policies since the end of the Cold
War are having an important
positive -- impact.
Andrew Mack is director and
Sebastian Merz is associate director of the Human Security Report Project
at the School for International Studies at Simon Fraser University in Vancouver.
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