that started in the late 1950s did not pick up steam or run out of it in tandem with the ups and downs of the business cycle. And they are not automatic outcomes of modern affluence, as we see in the relatively high tolerance of domestic violence and the spanking of children in some well-to-do Asian states (chapter 7).
Nor does violent crime closely track the economic indicators. The careenings of the American homicide rate in the 20th century were largely uncorrelated with measures of prosperity: the murder rate plunged in the midst of the Great Depression, soared during the boom years of the 1960s, and hugged new lows during the Great Recession that began in 2007 (chapter 3). The poor correlation could have been predicted by the police blotters, which show that homicides are driven by moralistic motives like payback for insults and infidelity rather than by material motives such as cash or food.
Wealth and violence do show a powerful connection in one comparison: differences among countries at the bottom of the economic scale (chapter 6). The likelihood that a country will be torn by violent civil unrest, as we saw, starts to soar as its annual per capita domestic product falls below $1,000. It’s hard, though, to pinpoint the causes behind the correlation. Money can buy many things, and it’s not obvious which of the things that a country cannot afford is responsible for its violence. It may be deprivations of individual people, such as nutrition and health care, but it also may be deprivations of the entire country, such as decent schools, police, and governments (chapter 6). And since war is development in reverse, we cannot even know the degree to which poverty causes war or war causes poverty.
And though extreme poverty is related to civil war, it does not seem to be related to genocide. Recall that poor countries have more political crises, and political crises can lead to genocides, but once a country has a crisis, poverty makes it no more likely to host a genocide (chapter 6). At the other end of the affluence scale, late 1930s Germany had the worst of the Great Depression behind it and was becoming an industrial powerhouse, yet that was when it brewed the atrocities that led to the coining of the word genocide.
The tangled relationship between wealth and violence reminds us that humans do not live by bread alone. We are believing, moralizing animals, and a lot of our violence comes from destructive ideologies rather than not enough wealth. For better or worse—usually worse—people are often willing to trade off material comfort for what they see as spiritual purity, communal glory, or perfect justice.
Religion. Speaking of ideologies, we have seen that little good has come from ancient tribal dogmas. All over the world, belief in the supernatural has authorized the sacrifice of people to propitiate bloodthirsty gods, and the murder of witches for their malevolent powers (chapter 4). The scriptures present a God who delights in genocide, rape, slavery, and the execution of nonconformists, and for millennia those writings were used to rationalize the massacre of infidels, the ownership of women, the beating of children, dominion over animals, and the persecution of heretics and homosexuals (chapters 1, 4, and 7). Humanitarian reforms such as the elimination of cruel punishment, the dissemination of empathy-inducing novels, and the abolition of slavery were met with fierce opposition in their time by ecclesiastical authorities and their apologists (chapter 4). The elevation of parochial values to the realm of the sacred is a license to dismiss other people’s interests, and an imperative to reject the possibility of compromise (chapter 9). It inflamed the combatants in the European Wars of Religion, the second-bloodiest period in modern Western history, and it continues to inflame partisans in the Middle East and parts of the Islamic world today. The theory that religion is a force for peace, often heard among the religious right and its allies today, does not fit the facts of history.
Defenders of religion claim that the two genocidal ideologies of the 20th century, fascism and communism, were atheistic. But the first claim is mistaken and the second irrelevant (chapter 4). Fascism happily coexisted with Catholicism in Spain, Italy, Portugal, and Croatia, and though Hitler had little use for Christianity, he was by no means an atheist, and professed that he was carrying out a divine plan.1 Historians have documented that many of the Nazi elite melded Nazism with German Christianity in a syncretic faith,