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Book Review: The Internationalists: How a Radical Plan to Outlaw War Remade the World


On a summer afternoon in 1928, world leaders assembled in Paris to outlaw war. Within a year, the treaty signed that day, known as the Peace Pact, was ratified by nearly every state in the world. Signed in the sweltering Quai D’orsay, war, for the first time in history, had become illegal. Within a decade, the states that signed the pact were again at war, and as a result, many dismissed the pact as folly. In their new book The Internationalists: How a Radical Plan to Outlaw War Remade the World, Oona Hathaway, and Scott Shapiro argue that this dismissal was mistaken and that the pact ushered in a sustained march towards peace. While doing so, they tell the history of how the pact came to be and of the lawyers, politicians, and intellectuals whose ideas have shaped our understanding of war’s role in just world order.

The treaty can be seen as the first milestone in human decency- by outlawing war as the norm. Or in other words, the Peace Pact shifts international law from pro-war to anti-war. It must be noted that (Peace Pact) did not create world peace. However, it was among the transformative events of human history. It has, nonetheless, made the world peaceful by it marking the beginning of the end of the replacement of one international order with another. The Pact furthers a trend that leads to other international treaties such as the UN Charter art 2(4). During his address, Frank Kellog noted that the treaty “marks a new date in the history of mankind, end of selfish and willful warfare”. To the authors in the Introduction note, if you want peace, prepare for peace- a play on the celebrated maxim of Roman Military theorist Vegetius: If you want peace, prepare for war.

On War

The authors further suggest that outlawing war seems 'ridiculous' to us because ours is a world in which war has already been outlawed. It is difficult to imagine war serving any legitimate function other than a defensive one. Today, war is regarded as a departure from civilized politics. Before 1928, war was not a departure from politics, it was civilized politics. The Pact has fundamentally altered the nature of conflict by outlawing war itself- it has reshaped the world map, catalyzed the human rights revolution, enabled the use of economic sanction as a tool of law enforcement, and ignited the explosion in the number of international organizations that regulate so many aspects of our daily lives. In essence, the Pact provided the way for treaties to create a positive obligation based on principles of natural law. However, let us recollect the time frame and understand that treaty formation does not alter state behavior instantly. This is especially true in the case of the Pact, that is because the treaty went into effect on July 24, 1929, after which the following occurred: Japan invaded Manchuria (1931); Italy invaded Ethiopia (1935); Japan invaded China (1937); Germany invaded Poland (1939); the Soviet Union invaded Finland (1939); Germany invaded Denmark, Norway, Belgium, the Netherlands, Luxembourg, and France and attacked Great Britain (1940); and Japan attacked the United States (1941), culminating in a global war that produced the atomic bomb and more than sixty million deaths.

A piece of paper signed in Paris does not seem to have presented an obstacle to citizens of one country engaging in the organized slaughter of the citizens of other countries.

The key figure in the early part of the story is Grotius, who, in contriving a legal justification for a Dutch seizure of Portuguese goods off Singapore, eventually produced a volume, "On the Laws of War and Peace," published in 1625, that Hathaway and Shapiro say became "the textbook on the laws of war." Grotius argued that wars of aggression are legal as long as states justify them, but that even when the justifications prove to be shams the winners have a right to keep whatever they have managed to seize. In Grotius's system, to use Hathaway and Shapiro's formulations, might makes right and possession is ten-tenths of the law.

Hathaway and Shapiro argue that Grotius's law of war explains why actions that look like simple land grabs, such as the Mexican-American War, which began in 1846, were perfectly legal undertakings. They explain that the United States had a valid justification for attacking Mexico—among other things, they say, there was a matter of unpaid debts—and that it also had a right to whatever territory it could lay claim to as a result, which, in that case, included all or part of what would become California, Utah, Nevada, Arizona, New Mexico, Colorado, and Wyoming. The Mexican-American War was not an extralegal military adventure. It was how nations behaved in what Hathaway and Shapiro call the Old World Order. The Old World Order set a low bar for going to war, which was convenient during a period of imperial expansion but dangerous when the imperial powers turned on one another. In 1914, Grotius's chickens came home to roost. The First World War was a regional brush fire that turned into an out-of-control inferno almost overnight. The system was not working, and the outlawry movement was a response to the emergency.

Division of Camps

It must also be noted that the Kellogg-Briand Pact had not made war a crime; it had simply removed the legal immunity that had been extended to it under Grotius's system. And, according to international law, states, rather than individuals, were responsible for war crimes. To prosecute the defendants at Nuremberg, the Allies and their lawyers had to convert the Pact into a criminal code that made individuals liable for illegal acts of war. They did, and that is the most important legacy of Nuremberg today. It is what has allowed the prosecution, in an international court in The Hague, of more than a hundred and fifty individuals for war crimes committed during the fighting that took place in the former Yugoslavia in the 1990s.

As Hathaway and Shapiro see it, the success in establishing this New World Order has brought "seven decades of unprecedented peace and prosperity." That success has come at a price, however. When the United Nations was founded, in 1945, there were fifty-one member states, and the architects of the U.N. buildings left room for twenty more. Today, there are a hundred and ninety-three U.N. members. This is, in part, because the ban on conquest has allowed small states to maintain their sovereignty. But it has also produced several internally weak states, and a great deal of the carnage around the world today is the result of intrastate conflicts or the emergence of militant groups in states whose governments lack the power to suppress them. The Islamic State is an example of the kind of insurgency that thrives in weakened regimes. Atrocities seem endemic to such intrastate conflicts.

Historical developments underlie many of the changes in the legal status of military conflict that Hathaway and Shapiro bring to our attention. So, for example, when they assert that "the likelihood that a state will suffer a conquest has fallen from once in a lifetime to once or twice in a millennium," and support the claim with data comparing the amount of territory conquered annually between 1816 and 1928 with the amount conquered annually after 1948—it was many times greater in the earlier period—they are only recording the difference between a period of intensive empire-building and a period of imperial divestment.

"It is likely no coincidence that Grotius's new theory favored sovereigns and their trading companies," Hathaway and Shapiro note. Well, yes. International law is the superstructure for the system of geopolitical relations. In writing his law of war, Grotius claimed to be deduced from the principles of natural law the proper rights of states. But he was induced from the actual actions and ambitions of powers like the Netherlands a set of rules that legalized their behavior. Ideas like Grotius's mattered because they provided a coherent rationale for what was happening in the world willy-nilly. Grotius made the world safe for imperialists.

It is not surprising that the great powers, in a world in which their influence and their share of the global product were likely to shrink, we're willing to exchange the right of conquest for globalization, with its system of international trade agreements. "The Pact appealed to the West because it promised to secure and protect previous conquests, thus securing Western Nations' place at the head of the international legal order indefinitely," as Hathaway and Shapiro rightly say. Defining "conquest" as a violation of international law today means that it is much harder for smaller states to become big ones, and making smaller countries dependent on their trade with bigger ones keeps them in line. That there will be better off and worse off is always implicit in the concept of order.


This is something that can be under-recognized in political histories, where the emphasis tends to be on material conditions and relations of power. Hathaway and Shapiro further believe that ideas are produced by human beings, something that can be under-recognized in intellectual histories, which often take the form of books talking to books. "The Internationalists" is a story about individuals who used ideas to change the world. Perhaps what remains debatable is whether or not the world order is a creation of global governance or merely a furtherance of alliance-building based on homogeneity of political theory norms. In other words, do Military Alliances like NATO rule the roost and control those exerting undue pressure, or is the world truly based on an international legal regime furthered by international organizations.

Furthermore, looking at it closely, one remains ambivalent on the alteration of the status quo to shift from war (or at least preparing for it) to global peace-building. Consider this, how does an American super capitalist structure wriggle itself out of this malaise of military spending in a democratic structure. The reasoning is as follows- big military manufacturing corporations like Lockheed Martin and Boeing guarantee jobs throughout America. These jobs vary in pay grade and function however are jobs spread across the country. The politicians base their manifesto on increasing and ensuring jobs. This guaranteed employment will be at risk if the defense contracts are severed (by reducing defense spending). In the end, jobs will be cut- and the lynchpin in this, the politician be willing to destroy his manifesto in the name of peace? Peace, which they define under the careful construction of self-defense and preparation to ensure a preemptive strike. Will then, lack of preparedness or 'peace'- be an alternative? Can they consider this viable politically or even, economically given how deeply the corporations have sunken their teeth with 'defense contracts' through preparation and consequent job creation for the masses. All things considered, imagining the absence of International law, in the 21st Century first century, in a Hobbesian sense would be a "dissolute condition of masterless men, without subjection to Laws, and a coercive power to tie their hands from rapine, and revenge" or in other more famous words, the life of man, solitary, poor, nasty, brutish, and short. Since tools of international law protect or at least safeguard us from tyranny.


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