“The United States entered the war in response to issues that still resonate—terror attacks on passenger travel and clandestine surveillance of and by foreign governments.”

By Christopher Kelly

ONE HUNDRED YEARS ago this week, President Woodrow Wilson ended America’s longstanding policy of isolation and led the United States into World War One on the Allied side.

More than two and a half million Americans were shipped “over there” to Europe where they would serve in the American Expeditionary Force (AEF). By war’s end, more than 100,000 of them would join the ranks of what British Prime Minister Lloyd George termed, without a trace of irony, “the glorious dead.”

Why did Wilson make his fateful decision to enter the “War to End all Wars”? Two of the principle reasons behind the president’s decision were the German policy of unrestricted submarine warfare and the Zimmerman Telegram.

The War At Sea

Unrestricted submarine warfare has become a stilted phrase that smacks of dry textbooks. It was not so then. The period prior to World War One was the golden age of the ocean liner. Aviator Charles Lindbergh did not fly across the Atlantic until 1927. The only practical way to travel between North America and Europe was via passenger ship. These vessels were the equivalent of commercial aircraft today.

Unrestricted submarine warfare would eventually lead to the sinking of the RMS Lusitania in 1915. A German U-boat torpedoed the liner off the coast of Ireland, killing around 1,200 passengers, including at least 125 U.S. citizens. The attack outraged America.

In 1916, Germany moderated its submarine policy by pledging not to attack ocean liners without providing for the safety of their passengers and crew. But on Jan. 31, 1917, Kaiser William II reversed course, ordering the resumption of unrestricted submarine warfare against Allied shipping. This desperate move aroused indignation in the United States and compelled President Wilson and Congress to declare war on Germany on April 6, 1917.

In order to appreciate the full horror of unrestricted submarine warfare, imagine how we might react today if a hostile nation state used jet fighters to shoot down commercial airliners flying toward the cities of its enemy.

Defending the Southern Border

The Zimmerman Telegram is a reminder that much of the “surveillance society” in which we live today had its origins in World War One espionage.

After the outbreak of hostilities, the British built a sophisticated signals intelligence network designed to monitor German radio traffic during the war. Room 40 was a decryption service of the British Admiralty that would later inspire the code breakers of Bletchley Park in World War Two. Their greatest coup of the war was the interception and decryption of the famous Zimmermann Telegram in 1917. This message, sent by the German minister of foreign affairs to the Mexican government, proposed an alliance with Mexico in the event of America’s entry into the war. Room 40 was also responsible for the capture of World War One’s most famous spy—the tragic case of Mata Hari.

World War One was a watershed event for the United States and the wider world. The conflict cost over 17 million lives and was dubbed the “suicide of civilization” by Pope Benedict XV. It toppled four empires and led directly to the creation of Syria and Iraq. The assassination of Archduke Ferdinand and his wife in Sarajevo had been the catalyst that first ignited the conflagration in 1914. But America entered the war in 1917 in response to issues that still resonate and have been further amplified in our own day—terror attacks on passenger travel and clandestine surveillance of and by foreign governments.

The Great War — A Personal Connection

My own great-uncle John Wells (1895–1951) was a member of the AEF. Wells served as a 2nd Lieutenant in the 27th Infantry, or New York Division.

He trained with the unit at Camp Wadsworth in South Carolina before deploying to Europe in May of 1918.

In the fall of 1918, this unit saw fierce action in the Somme push and along the Meuse River.

The New York Division helped to break the back of the German Army along the Hindenburg Line, leading to Germany’s surrender in November 1918.

Christopher Kelly is a history writer and the editor of An Adventure in 1914, a memoir written by Thomas Tileston Wells about his family’s voyage through Europe on the brink of World War One.