Oise-Aisne American Cemetery, Fere-en-Tardenois, near Chateau-Thierry, FranceAlden Bentley / Reuters

There are the wars we remember, and the wars that seem to drift away. Korea is one such, but at least there is a monument in Washington to the startled World War II veterans recalled from the post-1945 American recovery to do battle on those cold and barren hills. The doughboys of World War I do not even have that yet, although commissions and architects are actively bickering about what one might look like.

Worse yet, to the extent Americans remember World War I at all, it is as a futile war, a massive, utterly senseless butchery of a damned generation. That was not the way Americans at the time conceived it. More controversially, it is an excessively simple way of conceiving it even now.

I have on my desk a beautiful book, which shows what the Government Printing Office was once capable of. It is the second edition of American Armies and Battlefields in Europe: A History, Guide and Reference Book, prepared by the American Battle Monuments Commission in 1927, and updated thoroughly a decade later. It has meticulous directions to every American World War I battlefield; it is illustrated with abundant and exquisitely drawn multi-colored maps as well as photographs and exceptional sketches. My copy is 80 years old, and judging by the quality of paper and binding, it could last at least another 80. Itself something of a monument, it was designed to help guide veterans and their families returning to visit the newly peaceful fields of France.

Today, American tourists visit the haunting D-Day cemetery at Colleville-sur-Mer in Normandy in large numbers. Far fewer visit the Meuse Argonne cemetery near Verdun, although it is the largest of all such resting places in Europe, with 14,200 men and women of the American Expeditionary Force buried in orderly rows on its gentle rolling slopes. It is no less moving for all that—and indeed perhaps more so for its immaculately tended seclusion and loneliness. The truth is that Omaha Beach has a call on the public imagination that names like Chateau-Thierry once had and have now lost.

The World War I centennial matters far more in Europe than in the United States, which is understandable. For Europeans it is the great divide, the beginning of the short and awful 20th century that swept the continent with the two bloodiest wars in history, with revolution and the division of the home of Western civilization into blocs dominated by two superpowers who were at best only quasi-members of the European society of nations.

But Americans should still recall today that 100 years ago, in the summer of 1918, they were in the midst of a war that would ultimately cost their country more dead than Vietnam. Indeed, during the summer of that year the real struggles still lay ahead. Having entered the war in the spring of 1917 after much to-ing and fro-ing, the Americans were still gathering their strength. The Army of barely 120,000 was on its way to a more than 30-fold expansion.  A million soldiers had been shipped to France; before long more than 200,000 strapping young men were marching off the ships every month. The Americans had had some early successes, but the real test of the Meuse-Argonne offensive in September lay ahead. That fierce month-and-a-half long battle cost 26,000 American dead, or over six times as many as the D-Day landings.

Like their country, the soldiers of the AEF were abundant, enthusiastic, and ill-prepared for what awaited. Having foresworn military preparedness, the Wilson administration was woefully unready to wage war, as Theodore Roosevelt among others had warned. The statistics are startling: Not one American-made artillery shell was fired by the U.S. First Army (the Second Army showed up only at the very end); not one American-manufactured tank was deployed.  The United States Army had to buy some 4,500 artillery pieces and 9,600 machine guns from the French. American divisions were clumsily organized, and their logistics were, until near the end, an appalling mess.

Nor was the high command much to admire. General John “Black Jack” Pershing was adamantly determined to keep his forces separate and unified, even if it jeopardized the cohesion of a line that was close to breaking under the pressure of a series of offensives on the Western Front that the Germans launched in the spring and early summer of 1918. He believed, moreover, in aggressive tactics that reflected a naïve underestimate of how modern fire power had transformed the battlefield. Premier Georges Clemenceau of France sourly warned him that either the French could teach the Americans about modern battle, or the Germans would. To an unnecessary degree, Pershing opted for the latter.

The war shaped the careers of many officers who would lead the United States to its victories in the Second World War. George C. Marshall, as a colonel, was Pershing’s top planner. George Patton got his first taste of tank warfare. A crotchety naval captain, Ernest King, vowed that never again would the United States Navy play second fiddle to the Royal Navy. And a young assistant secretary of the Navy, Franklin Delano Roosevelt, learned lessons about leading a bureaucracy at war.

The American people celebrated the raw muscle that their country had displayed. The Chateau Thierry monument, near the site where the 3rd Infantry Division helped block one of the last German offensives and earned the nickname it bears to this day, “Rock of the Marne,” features an imposing eagle with the inscription “Time will not dim the glory of their deeds.” It is assertive and self-confident and thus different from the proud but somber French and British memorials of Verdun or the Menin Gate in Ypres.

But although these monuments were going up in the 1930s, they were accompanied by disillusionment and disgust with the war’s outcome. It had self-evidently proven not to be the war that would end all wars. It did not end power politics. It did not inaugurate an era of peace and brotherhood. It engendered no small suspicion that the government was controlled by cliques of warmongering economic interests. That suspicion helped produce the neutrality legislation that, in 1940, prevented the United States from rushing aid to a Britain now fighting for survival, alone. Above all, it convinced many Americans that they could, and should, withdraw behind their Atlantic and Pacific moats, and look to their own interests while the world went its own wicked ways.

The United States and the world paid a heavy price for those beliefs. A German victory in Europe was worth fighting to stop. It would have created an imperial power bound to clash with the United States, and indeed intent on so doing. It would have bred even more wars in its wake. The Versailles settlement of 1919 was flawed, but it was a remarkable achievement given the ruined world of 1918, and it could have been made to work—if the United States had displayed the statecraft that it did from 1945 to 1950. It chose not to. When Winston Churchill was asked during World War II what the conflict should be called, he replied: “The Unnecessary War.” American withdrawal from world affairs, and from concern with world order, helped create the conditions that made that second war possible.

There is a lesson here. And if the graves of the Meuse Argonne cemetery are not enough to make an American weary of global engagement reflect on that error, perhaps visits to the other resting places of American fallen in that second, unnecessary war—in Tunisia, or Italy, or Luxembourg, or England, or the Rhone Valley—will suffice.

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