We recently commemorated another “Veterans Day” — known by an earlier generation as Armistice Day. On November 11, 1918, the guns on the Western Front fell silent after more than four years of war. The First World War — what that earlier generation called the Great War — was over. Four imperial, religiously-inspired dynasties (Hapsburg, Hohenzollern, Romanov, and Ottoman) collapsed. Secular totalitarian ideologies rose to power in Russia, Italy, more than a decade later in Germany, and three decades later in China. The Great War was the great divide between a tradition-bound world and modernity. It was, in the American diplomat George Kennan’s words, the “seminal catastrophe” of the 20th century.

The Great War’s causes have long been debated. The Concert of Europe that established peace after the Napoleonic Wars started to fall apart in the mid-19th century when German Chancellor Otto von Bismarck fought three short wars to unify Germany and thereby upset the balance of power on the European continent. Bismarck, a statesman of rare genius, created alliances that imposed a fragile stability in Europe. When Bismarck left the scene in 1890, his system began to falter. Germany, already Europe’s greatest land power, challenged Great Britain at sea. Bismarck with remarkable foresight once remarked that the next major European war would result from “some damn fool thing in the Balkans.”

In the early years of the 20th century, a series of small crises increased tensions among the great powers, causing them to form opposing alliances. By 1914, all that was needed was a spark to ignite the cataclysm, and, as Bismarck predicted, the spark occurred in the Balkans when a Serbian terrorist assassinated the heir to the Austro-Hungarian throne in Sarajevo on June 28, 1914. Germany encouraged and supported the Austro-Hungarian ultimatum to Serbia, while Russia backed the Serbs. France had a treaty with Russia, while Great Britain ultimately backed France and Russia to try to maintain the European balance of power.

Although many historians still cling to the Barbara Tuchman view set forth in The Guns of August that the Great War broke out as a result of a series of unplanned events and accidents, German historian Fritz Fischer made a persuasive case in Germany’s Aims in the First World War and War of Illusions that the war resulted from Germany’s bid for world power.

The Great War was unlike any previous conflict. Perhaps no one better described the horrors of the Great War than Winston Churchill, who during that war served as First Lord of the Admiralty, Minister of Munitions, Secretary for Air and War, and as a front line combatant for about six months on the Western Front. In the first volume of The World Crisis, Churchill wrote:

The Great War through which we have passed differed from all ancient wars in the immense power of the combatants and their fearful agencies of destruction, and from all modern wars in the utter ruthlessness with which it was fought. All the horrors of all the ages were brought together, and not only armies but whole populations were thrust into the midst of them. The mighty educated States involved conceived with reason that their very existence was at stake. Germany having let Hell loose kept well in the van of terror; but she was followed step by step by the desperate and ultimately avenging nations she had assailed. Every outrage against humanity or international law was repaid by reprisals often on a greater scale and of longer duration. No truce or parley mitigated the strife of the armies. The wounded died between the lines: the dead mouldered into the soil. Merchant ships and neutral ships and hospital ships were sunk on the seas and all on board left to their fate, or killed as they swam. Every effort was made to starve whole nations into submission without regard to age or sex. Cities and monuments were smashed by artillery. Bombs from the air were cast down indiscriminately. Poison gas in many forms stifled or seared the soldiers. Liquid fire was projected upon their bodies. Men fell from the air in flames, or were smothered, often slowly, in the dark recesses of the sea. The fighting strength of armies was limited only by the manhood of their countries. Europe and large parts of Asia and Africa became one vast battlefield on which after years of struggle not armies but nations broke and ran. When all was over, Torture and Cannibalism were the only two expedients that the civilized, scientific, Christian States had been able to deny themselves: and these were of doubtful utility.

It is estimated that the Great War produced up to 40 million casualties (dead, wounded, missing). The actual number will never be known with certainty. Soldiers on the field were often hurriedly buried in bunches. Russia lost nearly 2 million dead and 5 million wounded. France suffered close to a million and a half dead and more than 4 million wounded. The British Empire (including Australians and Indians) lost a million dead and over 2 million wounded. Nearly 1.8 million German soldiers died and more than 4 million were wounded. Total casualties for Austria-Hungary were more than 4.5 million, of whom 1.2 million were killed. Nearly 117,000 American soldiers died in the war and more than 200,000 were wounded.

But the numbers of dead and wounded are only part of the tragedy of the Great War. The war cast a very long shadow. It ruptured the moral certainties of the 19th-century world. It confirmed for many that German philosopher Friedrich Nietzsche was right when he wrote (in 1882) that “God is dead.” It signaled the beginnings of the decline of Christianity and traditional religions and spawned the rise of secularism, including in its totalitarian incarnations of communism and fascism. When George Kennan looked back on the subsequent horrors of the 20th century — more destructive wars, genocides, Gulags, ethnic cleansings, cultural revolutions — he opined that all the lines of inquiry lead back to the Great War.

The Great War also resulted in an exponential growth of state power, confirming Randolph Bourne’s observation that “war is the health of the state.” As the great British historian Paul Johnson has explained, the growth of state power is one of the seminal and lasting developments of the 20th century, and this phenomenon continues in the 21st century. And as state power grows, individual freedom necessarily suffers. The “mighty educated States” that produced Churchill’s catalog of horrors in the Great War, went on to produce even greater horrors throughout the rest of the 20th century. (READ MORE: Lessons From Paul Johnson’s Modern Times)

Today, the People’s Republic of China is one of those “mighty educated States,” where the Communist Party has created what Stein Ringen calls “The Perfect Dictatorship.” China, whose laborers had aided Britain and France during the Great War, was angered when the great powers at Versailles awarded Chinese territory to Japan (who had contributed combat troops to the fighting). The May 4 protest movement in China was organized in response to China’s humiliation at Versailles, and it was that movement that led to the formation of the Chinese Communist Party (CCP) in 1921 — the very same party that today rules the country that seeks to replace the United States as the world’s leading power. The Great War casts a very long shadow.