It would have been much easier for my commentary to be colorful were the essay “A More Secure World” fatally flawed, but Andrew Mack has things about right. The world has become more peaceful, particularly in recent decades and in certain regions. Let me try to sharpen or emphasize a few points. I would also like to try to dive a bit deeper into the big “why” question. We all want to know whether this peace is temporary or perhaps perpetual.
A Few More Pictures of the Peace
It will help to begin with a few longer-term images of conflict trends. The graphs Mack provided are indicative, but we cannot really be sure a trend is a trend by looking at the bit that is supposed to be the anomaly. Below is a graph of the number of militarized interstate disputes—conflicts involving militarized threats, displays, or force up to and including major war between at least two countries—per year adjusted for the number of country pairs in the world. After an unusually violent period at the beginning of the 20th century, peace has begun to take hold. The trend Mack identifies is not only present post–Cold War, but has been a part of the modern world since at least the end of the Second World War. Countries are fighting each other less, and at all levels of conflict intensity.
It could also be that the last two centuries are the anomaly. To look back further, we need to focus on Europe, where data is slightly better. The next figure details conflict in Europe between 1400 and 2000. These data come from Peter Brecke. Warfare here represents at least 32 conflict-caused deaths, with each tiny square detailing the number of conflicts in a given decade. There is quite a bit of “noise” in the amount of conflict by decade, but clearly, too, there is a prevailing trend. These results are generally consistent with findings using other compilations of conflict behavior. Conflicts decrease in Europe from an average of 30 per decade at the beginning of the fifteenth century to about 10 per decade in 2000.
What is Going On?
So peace has broken out, at least in some places. Yet peace has been sought so earnestly, for such a long time, and with so little demonstrable success that it would be foolish, even irresponsible, for scholars to pretend that evidence alone is sufficient to have confidence in optimistic conclusions. History has observed other periods of unusual peace (there is an interesting set of studies showing that the Cold War peace was not statistically abnormal). As a matter of practical contingency, even in Europe war could recur at any time in large part because there is nothing in an anarchical world that prevents it from happening. In the absence a compelling explanation for why many nations are, and will remain at peace, we must allow for the possibility that macro-historical tendencies toward war will recur.
So what is happening? My answer is similar to Mack’s, but I will pose it in a slightly different way. First, let us think about why anyone (individuals, groups, nations) resorts to violence. War is costly and, in nominal terms, inefficient. Blood, effort, and treasure are expended in contests that might well be used in other ways. Yet historically, these actors return to violence because it offers the potential to accomplish ends for which they strive.
Conflict has utility in politics for one of two reasons. Either actors want physical, tangible stuff (populations, minerals, or territory) that they cannot all have, or they want intangible states of the world (policies, prerogatives, political concessions) that they may not be able to share. Think of the difference here in terms of the Cold War, where opponents wanted to impose a state of the world on one another—the United States and the Soviet Union had policy differences but did not want to physically control one another’s territory—and a war like the First World War, where opponents had real, tangible territorial objectives.
A second, separate question, is what actors are willing and able to do about their conflicts. Individuals are much more likely to act violently against a neighbor, since they are close and there are many opportunities to interact. Similarly, neighboring states are historically much more likely to fight. At the same time, alternatives are important in terms of whether opportunity and willingness to fight result in violence. I may dispute my neighbor in court instead of with my fists, if this is an option. Nations can occasionally work out differences peacefully when there are dispute mechanisms that accomplish “warfare by proxy.”
Almost as informative as the decline in warfare has been where this decline is occurring. Traditionally, nations were constrained by opportunity. Most nations did not fight most others because they could not physically do so. Powerful nations, in contrast, tended to fight more often, and particularly to fight with other powerful states. Modern “zones of peace” are dominated by powerful, militarily capable countries. These countries could fight each other, but are not inclined to do so. At the same time, weaker developing nations that continue to exercise force in traditional ways are incapable of projecting power against the developed world, with the exception of unconventional methods, such as terrorism.
The world is thus divided between those who could use force but prefer not to (at least not against each other) and those who would be willing to fight but lack the material means to fight far from home. Warfare in the modern world has thus become an activity involving weak (usually neighboring) nations, with intervention by powerful (geographically distant) states in a policing capacity. So, the riddle of peace boils down to why capable nations are not fighting each other. There are several explanations, as Mack has pointed out.
The easiest, and I think the best, explanation has to do with an absence of motive. Modern states find little incentive to bicker over tangible property, since armies are expensive and the goods that can be looted are no longer of considerable value. Ironically, this is exactly the explanation that Norman Angell famously supplied before the World Wars. Yet, today the evidence is abundant that the most prosperous, capable nations prefer to buy rather than take. Decolonization, for example, divested European powers of territories that were increasingly expensive to administer and which contained tangible assets of limited value.
Of comparable importance is the move to substantial consensus among powerful nations about how international affairs should be conducted. The great rivalries of the twentieth century were ideological rather than territorial. These have been substantially resolved, as Francis Fukuyama has pointed out. The fact that remaining differences are moderate, while the benefits of acting in concert are large (due to economic interdependence in particular) means that nations prefer to deliberate rather than fight. Differences remain, but for the most part the capable countries of the world have been in consensus, while the disgruntled developing world is incapable of acting on respective nations’ dissatisfaction.
While this version of events explains the partial peace bestowed on the developed world, it also poses challenges in terms of the future. The rising nations of Asia in particular have not been equal beneficiaries in the world political system. These nations have benefited from economic integration, and this has proved sufficient in the past to pacify them. The question for the future is whether the benefits of tangible resources through markets are sufficient to compensate the rising powers for their lack of influence in the policy sphere. The danger is that established powers may be slow to accommodate or give way to the demands of rising powers from Asia and elsewhere, leading to divisions over the intangible domain of policy and politics. Optimists argue that at the same time that these nations are rising in power, their domestic situations are evolving in a way that makes their interests more similar to the West. Consumerism, democracy, and a market orientation all help to draw the rising powers in as fellow travelers in an expanding zone of peace among the developed nations. Pessimists argue instead that capabilities among the rising powers are growing faster than their affinity for western values, or even that fundamental differences exist among the interests of first- and second-wave powers that cannot be bridged by the presence of market mechanisms or McDonald’s restaurants.
If the peace observed among western, developed nations is to prove durable, it must be because warfare proves futile as nations transition to prosperity. Whether this will happen depends on the rate of change in interests and capabilities, a difficult thing to judge. We must hope that the optimistic view is correct, that what ended war in Europe can be exported globally. Prosperity has made war expensive, while the fruits of conflict, both in terms of tangible and intangible spoils have declined in value. These forces are not guaranteed to prevail indefinitely. Already, research on robotic warfare promises to lower the cost of conquest. If in addition, fundamental differences among capable communities arise, then warfare over ideology or policy can also be resurrected. We must all hope that the consolidating forces of prosperity prevail, that war becomes a durable anachronism.