Today marks the one-hundredth anniversary of the event that triggered the outbreak of World War I. On a Sunday morning, June 28, 1914, Archduke Franz Ferdinand—nephew of the Austro-Hungarian Emperor Franz Josef and heir to his throne—was assassinated as his motorcade made its way through Sarajevo on the final day of a state visit to Bosnia. Despite the shocking character of the shooting, which also claimed the life of the Archduke’s wife Sophia, it was not expected that the killing of the scion of the Hapsburg dynasty would have particularly significant consequences.

However, in the course of July 1914 the crisis that followed the assassination steadily escalated. The response of the major European capitalist states was conditioned by tensions generated by conflicting geopolitical and economic interests that had been building up over the previous decade. The reactionary Hapsburg monarchy seized upon the assassination as a pretext for an attack on the Serbian regime, whose nationalist aspirations challenged the Austro-Hungarian Empire’s domination of the Balkans.

In Berlin, the regime of Emperor Wilhelm II gave the Austro-Hungarian government a green light to confront the Serbs with an all but unacceptable ultimatum that would lead to war. It took this action knowing that an Austrian invasion of Serbia would lead to an intervention by the Russian Empire to protect its interests in the Balkans. The German regime saw the prospect of a major war with Russia as an opportunity to establish its dominance in Eastern Europe and, thus, change the balance of power throughout the continent.

This prospect, however, frightened the ruling class in France, which had entered into an alliance with Russia to block the growth of German power. In the event of a war between Germany and Russia, the French bourgeoisie was convinced that it could not stand aside and accept a German victory. At the same time, the German regime had prepared, long in advance, detailed plans for an attack on France if war broke out with Russia.

The crisis led to a catastrophic denouement. By the first week of August, the major powers in Europe—Germany and Austro-Hungary on one side and France, Russia and Great Britain on the other—were in a state of war.

There have been countless volumes written analyzing the sequence of events that led from the assassination in Sarajevo on June 28 to a full-scale European war by the first week of August. Much of this literature has sought to establish which regime bore primary responsibility for the outbreak of war. But while the research has led to the discovery of important information related to the war aims of one or another government—such as, for example, the far-ranging ambitions of the German regime—the essential causes of the war require a deeper level of analysis.

The assassination in Sarajevo was no more than a spark that ignited the highly inflammable structure of European and international geopolitics. While it is possible that war might not have broken out in August 1914 if the Archduke had not been assassinated, some other event would have led—sooner rather than later—to a general war.

In fact, during the years preceding the outbreak of World War I, there had been a series of “war scares” arising from conflicts between the major capitalist powers over colonial and financial interests. The political climate of Europe had become increasingly tense. State spending on armaments had risen dramatically during the first decade of the twentieth century.

The growing socialist movement of the working class—under the banner of the Second International—became increasingly alarmed at the dangers posed by capitalist militarism. The potential for war between the “Great Powers” had emerged from the nature of the capitalist system. As early as 1902, the Marxist theoretician, Rudolf Hilferding, warned that the “sharpening of the struggle for the world market cannot remain without consequences for the foreign policy of the capitalist nations.” He noted that “increase in armaments, growth of the navy, internal reaction, violence and threats to peace in foreign relations, those are the necessary consequences of the newest phase of capitalist commercial policy.” [Cited in Discovering Imperialism: Social Democracy to World War I, edited by Richard B. Day and Daniel Gaido (Chicago, 2011), pp. 348-49]

As the decade progressed and the disastrous implications of imperialism became more and more apparent, the struggle against war was placed at the center of the work of the Second International. At its congress in Stuttgart in 1907, the Second International denounced colonialism, declaring that it “must lead to enslavement, forced labor, or the extermination of the native population of the colonialized regions. The civilizing mission that capitalist society claims to serve is no more than a veil for its lust for conquest and exploitation.” [Ibid, p. 28]

Five years later, at its Congress in Basel in 1912, the Second International issued a manifesto in which it declared:

If a war threatens to break out, it is the duty of the working classes and their parliamentary representatives in the countries involved… to exert every effort in order to prevent the outbreak of war by the means they consider most effective… In case war should break out anyway it is their duty to intervene in favor of its speedy termination and with all their powers to utilize the economic and political crisis created by the war to arouse the people and thereby to hasten the downfall of capitalist class rule.

But when the war broke out less than two years later, the leaders of the Second International repudiated their solemn commitment. On August 4, 1914, the largest and most politically influential section of the International, the German Social Democratic Party (SPD), voted to grant financial credits to the government, enabling it to prosecute the war. This act of political treachery marked the end of the Second International as a revolutionary force. The task of rebuilding a revolutionary International fell to those who opposed the capitulation of the Second International to the national ruling classes and to imperialism. Vladimir Lenin played the leading role in this struggle. His opposition to the war and defense of socialist internationalism laid the foundation for the victory of the socialist revolution in Russia in October 1917.

In opposition to all those in the Second International who justified their betrayal by absolving their own governments of responsibility for the outbreak of war, Lenin insisted that the war had grown out of the politics and economics of imperialism, and that all the governments were guilty. Subsequent research has confirmed Lenin’s indictment. Each government was determined to defend the global interests of the capitalist class of its own country. As one historian has written, “For virtually all of them, war was no longer the worst option.” [ The Arming of Europe and the Making of the First World War, by David G. Herrmann (Princeton, 1996), p. 226]

The World War was not an accident, the unintended result of policy mistakes. It arose inexorably from the contradictions of the capitalist system and the system of national states. Shortly after the war began, another revolutionary opponent of the betrayal of the Second International, Leon Trotsky, explained the historical significance of the war:

The War proclaims the downfall of the national state. Yet at the same time it proclaims the downfall of the capitalist system of economy…

The War of 1914 is the most colossal breakdown in history of an economic system destroyed by its own inner contradictions.

But war was not the only form in which the contradictions of the economic system would find expression. Trotsky foresaw another outcome to the crisis of world capitalism:

Capitalism has created the material conditions of a new socialist economic system. Imperialism has led the capitalist nations into historic chaos. The war of 1914 shows the way out of this chaos by violently urging the proletariat on to the path of Revolution. [ War and the International (Colombo, 1971) p. vii-viii]

One hundred years have passed since Sarajevo. In the course of a century, humanity has passed through two devastating world wars that cost the lives of tens of millions. The innumerable local wars incited by imperialism since the end of World War II have cost the lives of tens of millions more. And now, yet another global conflagration is being prepared.

Mankind cannot survive another world war, which would inevitably be waged with nuclear weapons. Such a catastrophe must be prevented.

The International Committee of the Fourth International observes this solemn anniversary by calling upon workers and youth throughout the world to take up the struggle against imperialism and war.