A few years ago, I published a book called 21 Lessons for the 21st Century, and dedicated one of the chapters to the future of war. Subtitled “Never underestimate human stupidity,” this chapter argued that the first decades of the 21st century had been the most peaceful era in human history, and that waging war no longer made much economic or geopolitical sense. But these facts did not absolutely guarantee peace, because “human stupidity is one of the most important forces in history” and “even rational leaders frequently end up doing very stupid things.”
Despite these reflections, in February 2022 I was shocked when Vladimir Putin tried to conquer Ukraine. The expected repercussions for Russia itself, and for the whole of humanity, were so destructive that it seemed an unlikely move even for a coldhearted megalomaniac. Yet the Russian autocrat chose to end the most peaceful era in human history, and to push humanity toward a new era of war that might be worse than anything we have seen before. Indeed, it might threaten the very survival of our species.
This is a tragedy, especially as the past few decades have shown that war isn’t an inevitable force of nature. It is a human choice that varies from place to place and time to time. Since 1945, we have not seen a single case of war between great powers, nor a single case of an internationally recognized state annihilated through foreign conquest. More limited regional and local conflicts remained relatively common; I live in Israel, so I know this perfectly well. But the Israeli occupation of the West Bank notwithstanding, countries have rarely tried to unilaterally expand their borders through violence. That’s one reason the Israeli occupation has drawn so much attention and criticism. What was the norm for thousands of years of imperial history has become anathema.
Even when taking civil wars, insurgencies, and terrorism into account, in recent decades wars have killed far fewer people than suicide, road accidents, or obesity-related diseases. In 2019, about 70,000 people were killed in armed conflicts or police shootings, about 700,000 people committed suicide, 1.3 million people died in road accidents, and 1.5 million people died from diabetes.
Yet peace has not been just a matter of numbers. Perhaps the most important change in recent decades has been psychological. For thousands of years, peace meant “the temporary absence of war.” For example, in between the three Punic Wars fought by Rome and Carthage were decades of peace, but every Roman and Carthaginian knew that this “Punic Peace” could be shattered at any moment. Politics, economics, and culture were all shaped by constant expectations of war.
During the late 20th century and early 21st century, the meaning of the word peace changed. Whereas the Old Peace meant only “the temporary absence of war,” the New Peace came to mean “the implausibility of war.” In many (though not all) regions of the world, countries stopped fearing that their neighbors might invade and annihilate them. Tunisians stopped dreading an Italian invasion, Costa Ricans didn’t think that the Nicaraguan army might make a dash to San José, and Samoans didn’t fear that a Fijian war fleet might suddenly emerge from beyond the horizon. How can we tell that countries weren’t concerned about these things? By looking at their state budgets.
Until recently, the military was the expected No. 1 item on the budget of every empire, sultanate, kingdom, and republic. Governments spent little on health care and education, because most of their resources went to paying soldiers, constructing walls, and building warships. The Roman Empire spent about 50 to 75 percent of its budget on the military; the figure was about 80 percent in the Sung Empire (960–1279); and about 60 percent in the late-17th-century Ottoman Empire. From 1685 to 1813, the share of the military in British government expenditure never fell below 55 percent and averaged 75 percent. During the great conflicts of the 20th century, democracies and totalitarian regimes alike plunged into debt to finance their machine guns, tanks, and submarines. When we fear that the neighbors might at any moment invade, loot our cities, enslave our people, and annex our land, that’s the reasonable thing to do.
State budgets in the era of the New Peace make for far more hopeful reading material than any pacifist tract ever composed. In the early 21st century, the average government expenditure on the military has been only 6.5 percent, and even the United States, the dominant superpower, has spent only about 11 percent to maintain its supremacy. Because people no longer lived in terror of external invasion, governments could invest far more money in health care, welfare, and education than in the military. Average expenditure on health care, for example, has been 10.5 percent of the government budget, or about 1.6 times the defense budget. For many people today, the fact that the health-care budget is bigger than the military budget is unremarkable. But if we take the New Peace for granted and therefore neglect it, we will soon lose it.
The New Peace was the outcome of three main forces. First, technological changes, and above all the development of nuclear weapons, greatly increased the price of war, especially between superpowers. The atomic bomb turned superpower war into a mad act of collective suicide, which is why superpowers have not gone to war directly against one another since Hiroshima and Nagasaki.
Secondly, economic changes greatly decreased the profits of war. Key economic assets were once material resources that could be conquered by force. When Rome defeated Carthage in the Punic Wars, it became rich by looting its defeated rival, selling its people into slavery, and taking over the silver mines of Spain and the wheat fields of North Africa. In recent decades, however, scientific, technical, and organizational knowledge have become the most important economic assets in many places. Silicon Valley has no silicon mines. Trillion-dollar businesses such as Microsoft and Google are built on what’s in the minds of engineers and entrepreneurs rather than what’s in the ground under their feet. And whereas seizing silver mines by force is easy, you cannot acquire knowledge that way. This economic reality led to a sharp decline in the profitability of conquest.
Although wars over material resources continue to characterize certain parts of the world—such as the Middle East—the big economies of the post-1945 period grew without imperial conquest. Germany, Japan, and Italy saw their armies broken and their territories shrink—but after the war, their economies boomed. The Chinese economic miracle was achieved without engaging in any major war since 1979.
As I was writing these lines in early November, Russian soldiers were looting the Ukrainian city of Kherson, sending back to Russia trucks full of carpets and toasters that they’d stolen from Ukrainian homes. This will not make Russia rich, and it will not compensate the Russians for the enormous cost of the war. But as Putin’s invasion of Ukraine proves, technological and economic changes by themselves were not enough to produce the New Peace. Some leaders are so power-hungry and so irresponsible that they might begin a war even if it is economically ruinous to their country and pushes the whole of humanity toward nuclear Armageddon. Accordingly, the third essential pillar of the New Peace has been cultural and institutional.
Human societies were long dominated by militaristic cultures that viewed war as inevitable, and even desirable. Aristocrats in both Rome and Carthage believed that military glory was life’s crowning achievement and the ideal route to power and riches. Artists such as Virgil and Horace concurred, devoting their talents to singing of arms and warriors, glorifying bloody battles, and immortalizing brutal conquerors. During the New Peace era, artists turned their talents to exposing the horrors of war, while politicians sought to leave their mark by initiating health-care reforms rather than by looting foreign cities. Leaders throughout the world—influenced by the fear of nuclear war, by the changes in the nature of the economy, and by new cultural trends—joined forces to build a functioning global order that allowed countries to develop peacefully while restraining the occasional warmongers.
This global order has been based on liberal ideals, namely, that all humans deserve the same basic liberties; that no human group is inherently superior to all others; and that all humans share core experiences, values, and interests. These ideals encouraged leaders to avoid war and instead work together to protect our common values and to advance our common interests. The liberal global order linked the belief in universal values to the peaceful functioning of global institutions.
Although this global order was far from perfect, it improved the lives of people not just in the old imperial centers such as Britain and the United States, but also in many other parts of the world, from India to Brazil and from Poland to China. Countries in all continents benefited from the rise in global trade and investments, and almost all countries enjoyed a peace dividend. Not only could Denmark and Canada shift resources from tanks to teachers—Nigeria and Indonesia did the same.
Anyone who rants about the defects of the liberal global order should first answer one simple question: Can you please name the decade in which humankind was in better shape than in the 2010s? Which decade is your lost golden age? Is it the 1910s, with the First World War, the Bolshevik Revolution, Jim Crow, and European empires brutally exploiting much of Africa and Asia? Is it perhaps the 1810s, with the Napoleonic Wars reaching their bloody climax, Russian and Chinese peasants crushed by their aristocratic overlords, the East India Company securing its control of India, and slavery still legal in the United States, Brazil, and most other parts of the world? Perhaps you are dreaming of the 1710s, with the War of the Spanish Succession, the Great Northern War, the Mughal succession wars, and a third of children everywhere dying from malnutrition and disease before reaching adulthood?
The New Peace didn’t result from some divine miracle. It was achieved by humans making better choices and building a functioning global order. Unfortunately, too many people took this achievement for granted. Perhaps they assumed that the New Peace was guaranteed mainly by technological and economic forces, and that it could survive even without its third pillar—the liberal global order. Consequently, that order was first neglected and then attacked with growing ferocity.
The attack started with rogue states such as Iran and rogue leaders such as Putin, but by themselves, they were not strong enough to end the New Peace. What really undermined the global order was that both the countries that benefited most from it (including China, India, Brazil, and Poland) and the countries that built it in the first place (notably the U.K. and the United States) turned their backs on it. The Brexit vote and the election of Donald Trump in 2016 symbolized this turn.
Those who have challenged the global liberal order mostly didn’t wish for war. They just wanted to advance what they understood as the interests of their country, and they argued that each nation-state should defend and develop its own sacred identity and traditions. What they never explained was how all of these different nations would deal with one another in the absence of universal values and global institutions. The opponents of the global order did not offer any clear alternative. They seemed to think that somehow, the various nations would just get along fine, and the world would become a network of walled-but-friendly fortresses.
Fortresses are seldom friendly, however. Each national fortress usually wants a bit more land, security, and prosperity for itself at the expense of its neighbors, and without the help of universal values and global institutions, rival fortresses cannot agree on any common rules. The network-of-fortresses model was a recipe for disaster.
And disaster was not long in coming. The pandemic demonstrated that in the absence of effective global cooperation, humanity cannot protect itself against common threats such as viruses. Then, perhaps because he observed how COVID further eroded global solidarity, Putin concluded that he could mete out the coup de grâce by breaking the biggest taboo of the New Peace era. Putin thought that if he conquered Ukraine and absorbed it into Russia, some countries would gasp in disbelief and condemn him—but nobody would take any effective action against him.
The argument that Putin was pushed unwillingly to invade Ukraine to preempt a Western attack is nonsensical propaganda. Some vague Western threat is not a legitimate excuse for destroying a country, looting its cities, raping and torturing its citizens, and inflicting untold suffering on tens of millions of men, women, and children. Anyone who believes that Putin had no choice should name the country that was preparing to invade Russia in 2022. Do you think the German army was massing to cross the border? Do you imagine that Napoleon got out of his grave to lead the Grande Armée yet again to Moscow, and Putin had no choice but to preempt the imminent French onslaught? And remember that Putin actually first invaded Ukraine back in 2014—not in 2022.
Putin prepared his invasion for a long time. He never accepted the breakup of the Russian Empire, and he never saw Ukraine, Georgia, or any of the other post-Soviet republics as legitimate independent nations. Whereas—as noted earlier—average military expenses have been about 6.5 percent of government budgets around the world and 11 percent in the United States, in Russia they have been far higher. We don’t know exactly how much higher, because it is a state secret. But estimates put the figure somewhere in the vicinity of 20 percent, and it may even be more than 30 percent.
If Putin’s gamble succeeds, the result will be the final collapse of the global order and of the New Peace. Autocrats around the world will learn that wars of conquest are again possible, and democracies, too, will be forced to militarize themselves for protection. We’ve already seen Russian aggression prompt countries such as Germany to sharply increase their defense budget overnight, and countries such as Sweden to reinstate conscription. The money that should go to teachers, nurses, and social workers will instead go to tanks, missiles, and cyberweapons. At 18, young people all over the world will do their mandatory military service. The whole world will look like Russia—a country with an oversize army and understaffed hospitals. A new era of war, poverty, and disease will result. Alternatively, if Putin is stopped and punished, the global order won’t be broken by what he did—it will be strengthened. Anyone who needed a reminder would rediscover that you just cannot do these things.
Which of these two scenarios will materialize? Luckily for everyone, despite his military preparations, Putin was disastrously unprepared for one crucial thing: the courage of the Ukrainian people. The Ukrainians have pushed back the Russians in a series of stunning victories near Kyiv, Kharkiv, and Kherson. But Putin has so far refused to acknowledge his mistake, and he reacts to defeat with increased brutality. Seeing that his army cannot overcome the Ukrainian soldiers on the front line, Putin is now trying to freeze the Ukrainian civilians to death in their homes. Predicting how the war will end is impossible, as is the fate of the New Peace.
History is never deterministic. After the end of the Cold War, many people thought that peace was inevitable, and that it would continue even if we neglected the global order. After Russia invaded Ukraine, some swung to the opposite view. They claimed that peace had always been just an illusion, that war was an ungovernable force of nature, and that the only choice humans had was whether they wanted to be prey or predator.
Both positions are wrong. War and peace are decisions, not inevitabilities. Wars are made by people, not by a law of nature. And just as humans make wars, humans can also make peace. But to make peace is not a one-off decision. It’s a long-term effort to protect universal norms and values, and to build cooperative institutions.
Rebuilding the global order doesn’t mean going back to the system that disintegrated in the 2010s. A new and better global order should give more important roles to non-Western powers that are willing to be part of it. It should also recognize the salience of national loyalties. The global order disintegrated above all because of the assault of populist forces, which argued that patriotic loyalties contradict global cooperation. Populist politicians preached that if you are a patriot, you must oppose global institutions and global cooperation. But there is no inherent contradiction between patriotism and globalism, because patriotism isn’t about hating foreigners. Patriotism is about loving your compatriots. And in the 21st century, if you want to protect your compatriots from war, pandemic, and ecological collapse, the best way to do that is by cooperating with foreigners.