Geoffrey Blainey

The Causes of War

The idea that an even distribution of power promotes peace has gained strength partly because it has never been accompanied by tangible evidence. Like a ghost it has not been captured and examined for pallor and pulsebeat. And yet there is a point of time when the ghost can be captured. The actual distribution of power can be measured at the end of the war.

The military power of rival European alliances was most imbalanced, was distributed most unevenly, at the end of a decisive war. And decisive wars tended to lead to longer periods of international peace. Indecisive wars, in contrast, tended to produce shorter periods of peace. Thus the eighteenth century was characterised by inconclusive wars and by short periods of peace. During the long wars one alliance had great difficulty in defeating the other. Many of the wars ended in virtual deadlock: military power obviously was evenly balanced. Such wars tended to lead to short periods of peace. The War of the Polish Succession—basically an ineffectual war between France and Austria—was followed within five years by the War of the Austrian Succession. That war after eight years was so inconclusive on most fronts that the peace treaty signed in 1748 mainly affirmed the status quo. That ineffectual war was followed only eight years later by another general war, the Seven Years War, which ended with Britain the clear victor in the war at sea and beyond the seas, though on European soil the war was a stalemate. But even the Anglo-French peace which followed the Treaty of Paris in 1763 was not long; it ended after fifteen years. It ended when the revolt of the American colonies against Britain removed Britain's preponderance of power over France.

The French Revolutionary Wars which, beginning in 1792, raged across Europe and over the sea for a decade were more decisive than any major war for more than a century. They ended with France dominant on the continent and with England dominant at sea and in America and the East. They thus failed to solve the crucial question: was England or France the stronger power? The Peace of Amiens, which England and France signed in 1802, lasted little more than a year. So began the Napoleonic Wars which at last produced undisputed victors.

This is not to suggest that a general war which ended in decisive victory was the sole cause of a long period of peace. A decisive general war did not always lead to a long period of peace. This survey of the major wars of the period 1700 to 1815 does suggest however that the traditional theory which equates an even balance of power with peace should be reversed. Instead a clear preponderance of power tended to promote peace.

Of the general wars fought in Europe in the last three centuries those with the most decisive outcome were the Napoleonic (1815), Franco-Prussian (1871), First World War (1918), and Second World War (1945). The last days of those wars and the early years of the following periods of peace marked the height of the imbalance of power in Europe. At the end of those wars the scales of power were so tilted against the losers that Napoleon Bonaparte was sent as a captive to an island in the South Atlantic, Napoleon III was captured and permitted to live in exile in England, Kaiser Wilhelm II went into exile in Holland and Adolf Hitler committed suicide. Years after the end of those wars, the scales of power were still strongly tilted against the losers. And yet those years of extreme imbalance marked the first stages of perhaps the most pronounced periods of peace known to Europe in the last three or more centuries.

Exponents of the virtues of an even distribution of military power have concentrated entirely on the outbreak of war. They have ignored however the conditions surrounding the outbreak of peace. By ignoring the outbreak of peace they seem to have ignored the very period when the distribution of military power between warring nations can be accurately measured. For warfare is the one convincing way of measuring the distribution of power. The end of a war produces a neat ledger of power which has been duly audited and signed.

According to that ledger an agreed preponderance of power tends to foster peace. In contrast the exponents of the orthodox theory examine closely the prelude to a war, but that is a period when power is muffled and much more difficult to measure. It is a period characterised by conflicting estimates of which nation or alliance is the most powerful. Indeed one can almost suggest that war is usually the outcome of a diplomatic crisis which cannot be solved because both sides have conflicting estimates of their bargaining power.

The link between a diplomatic crisis and the outbreak of war seems central to the understanding of war. That link however seems to be misunderstood. Thus many historians, in explaining the outbreak of war, argue that 'the breakdown in diplomacy led to war.' This explanation is rather like the argument that the end of winter led to spring: it is a description masquerading as an explanation. In fact that main influence which led to the breakdown of diplomacy—a contradictory sense of bargaining power—also prompted the nations to fight. At the end of a war the situation was reversed. Although I have not come across the parallel statement—'so the breakdown of war led to diplomacy'—it can be explained in a similar way. In essence the very factor which made the enemies reluctant to continue fighting also persuaded them to negotiate. That factor was their agreement about their relative bargaining position.

It is not the actual distribution or balance of power which is vital: it is rather the way in which national leaders think that power is distributed. In contrast orthodox theory assumes that the power of nations can be measured with some objectivity. It assumes that, in the pre-nuclear era, a statesman's knowledge of the balance of international power rested mainly on an 'objective comparison of military capabilities.' I find it difficult however to accept the idea that power could ever be measured with such objectivity. The clear exception was at the end of wars—the points of time which theorists ignore. Indeed, it is the problem of accurately measuring the relative power of nations which goes far to explain why wars occur. War is a dispute about the measurement of power. War marks the choice of a new set of weights and measures.

In peace time the relations between two diplomats are like relations between two merchants. While the merchants trade in copper or transistors, the diplomats' transactions involve boundaries, spheres of influence, commercial concessions and a variety of other issues which they have in common. A foreign minister or diplomat is a merchant who bargains on behalf of his country. He is both buyer and seller, though he buys and sells privileges and obligations rather than commodities. The treaties he signs are simply more courteous versions of commercial contracts.

The difficulty in diplomacy, as in commerce, is to find an acceptable price for the transaction. Just as the price of merchandise such as copper roughly represents the point where the supply of copper balances the demand for it, the price of a transaction in diplomacy roughly marks the point at which one nation's willingness to pay matches the price demanded by the other. The diplomatic market however is not as sophisticated as the mercantile market. Political currency is not so easily measured as economic currency. Buying and selling in the diplomatic market is much closer to barter, and so resembles an ancient bazaar in which the traders have no accepted medium of exchange. In diplomacy each nation has the rough equivalent of a selling price—a price which it accepts when it sells a concession—and the equivalent of a buying price. Sometimes these prices are so far apart that a transaction vital to both nations cannot be completed peacefully; they cannot agree on the price of the transaction. The history of diplomacy is full of such crises. The ministers and diplomats of Russia and Japan could not agree in 1904, on the eve of the Russo-Japanese War; the Germans could not find acceptable terms with British and French ministers on the eve of the Second World War.

A diplomatic crisis is like a crisis in international payments; like a crisis in the English pound or the French franc. In a diplomatic crisis the currency of one nation or alliance is out of alignment with that of the others. These currencies are simply the estimates which each nation nourishes about its relative bargaining power. These estimates are not easy for an outsider to assess or to measure; and yet these estimates exist clearly in the minds of the ministers and diplomats who bargain.

For a crisis in international payments there are ultimate solutions which all nations recognise. If the English pound is the object of the crisis, and if its value is endangered because England is importing too much, the English government usually has to admit that it is living beyond its present means. As a remedy it may try to discourage imports and encourage exports. It may even have to declare that the value of the English pound is too high in relation to the French franc, the German mark and all other currencies, and accordingly it may fix the pound at a lower rate. Whichever solution it follows is not pleasant for the national pride and the people's purse. Fortunately there is less shame and humiliation for a nation which has to confess that its monetary currency is overvalued than for a country which has to confess that its diplomatic currency is overvalued. It is almost as if the detailed statistics which record the currency crisis make it seem anonymous and unemotional. In contrast a diplomatic crisis is personal and emotional. The opponent is not a sheet of statistics representing the sum of payments to and from all nations: the opponent is an armed nation to which aggressive intentions can be attributed and towards whom hatred can be felt.

A nation facing a payments crisis can measure the extent to which it is living beyond its means. As the months pass by, moreover, it can measure whether its remedies have been effective, for the statistics of its balance of payments are an accurate guide to the approach of a crisis and the passing of crisis. On the other hand a deficit in international power is not so easy to detect. A nation with an increasing deficit in international power may not even recognise its weaknesses. A nation may so mistake its bargaining power that it may make the ultimate appeal to war, and then learn through defeat in warfare to accept a humbler assessment of its bargaining position.

The death-watch wars of the eighteenth century exemplified such crises. A kingdom which was temporarily weakened by the accession of a new ruler or by the outbreak of civil unrest refused to believe that it was weaker. It usually behaved as if its bargaining position were unaltered. But its position, in the eyes of rival nations, was often drastically weaker. Negotiations were therefore frustrated because each nation demanded far more than the other was prepared to yield. Likewise the appeal to war was favoured because each side believed that it would win.

In diplomacy some nations for a long period can live far beyond their means: to live beyond their means is to concede much less than they would have to concede if the issue was resolved by force. A government may be unyielding in negotiations because it predicts that its adversary does not want war. It may be unyielding because it has an inflated idea of its own military power. Or it may be unyielding because to yield to an enemy may weaken its standing and grip within its own land. Whereas an endangered nation facing a currency crisis cannot escape some punishment, in a diplomatic crisis it can completely escape punishment so long as the rival nation or alliance does not insist on war. Thus diplomacy may become more unrealistic, crises may become more frequent, and ultimately the tension and confusion may end in war.

Disputes about bargaining power will not necessarily matter if two nations have only slight contacts with one another. Prussia and Afghanistan in the nineteenth century probably had completely contradictory estimates of their own bargaining power, but this did not matter. But if two adjacent nations, Prussia and France, had contradictory estimates of their own bargaining power, the contradiction could be dangerous. Their estimates of their own strength for instance were contradictory in 1870. Each nation went to war, relatively confident that it would defeat the other. The more contact which nations have with one another, the more important it is that they should agree about their relative bargaining power. It has long been noticed that adjacent nations fight one another more frequently than they fight isolated nations.

A pioneer of sociology, Georg Simmel, while lecturing in philosophy at Berlin in 1904, set out a sad truth about international relations. He argued that the most effective way of preventing a war was to possess exact knowledge of the comparative strength of the two rival nations or alliances. And his exact knowledge, he wrote, 'is very often attainable only by the actual fighting out of the conflict.' Ironically he moved in 1914 from Berlin to Strasbourg, a city which Germany had annexed at the end of the Franco-Prussian War in 1871; and he was there when Germany and France again sought, through warfare, to learn exact knowledge of their comparative strength. That war ended with the defeat of Germany; and diplomatically she was weak throughout the 1920s. France had the bargaining power; differences could be resolved. Their relationship was dramatically altered in the 1930s when Germany rearmed herself. The German leaders' estimate of their nation's military strength now contradicted that which the French and British leaders held of their relative military strength. And if Georg Simmel, the German philosopher, had been alive during the Munich crisis of 1938, he might have predicted that the likely way of resolving the contradiction was through war.

War itself provides the most reliable and most objective test of which nation or alliance is the most powerful. After a war which ended decisively, the warring nations agreed on their respective strength. The losers and the winners might have disagreed about the exact margin of superiority; they did agree however that decisive superiority existed. A decisive war was therefore usually followed by an orderly market in political power, or in other words peace. Indeed one vital difference between the eighteenth and nineteenth centuries was that wars tended to become more decisive. This is part of the explanation for the war-studded history of one century and the relative peacefulness of the following century. Whereas the eighteenth century more often had long and inconclusive wars followed by short periods of peace, the century after 1815 more often had short and decisive wars and long periods of peace.

Nevertheless, during both centuries, the agreement about nations' bargaining power rarely lasted as long as one generation. Even when a war had ended decisively the hierarchy of power could not last indefinitely. It was blurred by the fading of memories of the previous war, by the accession of new leaders who blamed the old leaders for the defeat, and by the legends and folklore which glossed over past defeats. It was blurred by the weakening effects of internal unrest or the strengthening effects of military reorganisation, by economic and technical change, by shifts in alliances, and by a variety of other influences. So the defeated nation regained confidence. When important issues arose, war became a possibility. The rival nations believed they each could gain more by fighting than by negotiating. Those contradictory hopes are characteristic of the outbreak of war.