15th August 1917: A little girl has her hand shaken by an American soldier as his troop parade through the streets of London. (Photo by A. R. Coster/Topical Press Agency/Getty Images)
American cavalry standing upright on horses during training for their part in the First World War. (Photo by Topical Press Agency/Getty Images)
circa 1917: American General John "Black Jack" Pershing inspects U.S. troops. (Photo by Hulton Archive/Getty Images)
American troops carrying guns climb over a sandbag revetment in France during World War I in 1918. (AP Photo)
U.S. Artilleryman in doorway of his bombproof shelter in France, utilizes a few peaceful moments in writing to the folks at home on March 7, 1918. (AP Photo)
A suit of heavy metal-plated body armor used by the Americans in France in 1917. (Photo by Central Press/Getty Images)
Two United States soldiers run past the remains of two German soldiers toward a bunker. Note that this may well be a staged propaganda image. (National Archives)
An American airman sending off a carrier pigeon, circa 1917. (Photo by Topical Press Agency/Hulton Archive/Getty Images)
Two sailors in the crow's nest on board the American Battleship USS Kentucky. (Photo by Topical Press Agency/Getty Images)
A member of 5th Marine Regiment fires an anti-aircraft gun in Menaucourt, France, in 1918. exact date is unknown. (AP Photo)
US sailors aboard the USS Colorado, a Colorado-class battleship, during World War One, Portsmouth, Great Britain, circa 1914-1918. (Photo by Keystone/Getty Images)
The USS Saratoga formerley the USS New York (ACR-2) an Armoured cruiser of the United States Navy at anchor circa 1917 at Puget Sound Naval Shipyard, Bremerton, Washington, United States. (Photo by Paul Thompson/FPG/Getty Images)
U.S. soldiers wearing different styles of gas masks used by Allied and German forces during the First World War. (Photo by Hulton Archive/Getty Images)
An American doughboy from the First Division throws a hand grenade in battle during World War I along the Western Front in France on March 15, 1918. (AP Photo)
US Army 37-mm gun crew manning their weapon on September 26, 1918 during the World War I Meuse-Argonne (Maas-Argonne) Allied offensive, France. (AP Photo)
circa 1917: Members of the American Signal Corps carry a wounded comrade. (Photo by Hulton Archive/Getty Images)
America's top World War I air-ace Eddie Rickenbacker in the cockpit of his French-built SPAD 13. Rickenbacker survived the war with 26 'kills'. (Photo by Sgt Gideon J Eikleberry/Getty Images)
American soldiers of Battery C, 6th Field Artillery, firing their field gun surrounded by empty shell cases on the Lorraine front, Beaumont, France. (Photo by Sgt J A Marshall/Getty Images)
This picture, made at the close of World War I, shows allied officials dismounting from the railway car where they dictated the terms of the Armistice, Nov. 11, 1918. Gen. Maxime Weygand is second from left, Marshal Foch fourth from left. In this same car in Compiegne forest, Adolf Hitler handed France his armistice terms on June 21, 1940. (AP Photo)
American troops cheer after hearing the news that the Armistice has been signed, ending World War I in Nov. 1918. They are located on the front northeast of St. Mihiel, France. Similar celebrations took place all along the line where the Americans were engaged in an offensive. (AP photo)
New York troops in Corbie, France, celebrate the signing of the Armistice Treaty, Nov. 11, 1918. (AP Photo)
Peace celebrations in the USA after the signing of the Armistice Treaty, Nov. 11, 1918. (Photo by Topical Press Agency/Getty Images)