When the First World War engulfed Europe in August 1914 it was widely believed that sea power would be a decisive factor. In the decade before the war, Germany had begun to expand their fleet of battleships to challenge the dominance of British naval power. This arms race has been cited as one of the causes of the war.

Sea power was indeed decisive in the war. But it wasn’t the large fleets of giant battleships that were significant. In fact, the only large naval battle in the war, Jutland, in 1916, had no clear winner, and even today remains controversial. The real power of the sea came from the fleets of merchant ships bringing vast amounts of weapons, ammunition and raw materials to France, Britain, Russia and Italy—and after the U.S. entered the war, fresh troops by the million.

Through this same sea power a blockade denied food and weaponry to Germany and Austria. Do not underestimate the effect of this blockade: by the end of the war up to half a million people in the Central Powers had died of starvation and malnutrition because of it. As we noted in an editorial shortly after the war began, “food is as essential to success as guns.” [November 7, 1914]

The decisive fight at sea became a battle between fleets of cargo vessels escorted by naval surface ships against fleets of submarines. Those tasked with winning the war were under no illusion as to the importance of winning this battle.

For a more comprehensive look at all the aspects of World War I, military, economic, social, technological, see the World War I archive package at www.ScientificAmerican.com/wwi

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