Destroyers for bases

In the Destroyers for Bases Agreement between the United States and the United Kingdom on September 2, 1940, fifty mothballed Caldwell, Wickes, and Clemson-class US Navy destroyers were transferred to the Royal Navy from the United States Navy in exchange for land rights on British possessions. Generally referred to as the "twelve hundred-ton type" (also known as "flush-deck", or "four-pipers" after their four funnels), the destroyers became the Town-class and were named after towns common to both the United States and Britain. The agreement was a violation of the official neutral position of the United States.

The Second World War started in September 1939. After the eight month interlude of the Phony War, France and the Low Countries were quickly overrun by the Nazi German Blitzkrieg in the Battle of France in May 1940. This left the United Kingdom and British Empire fighting alone (or almost alone after the Italian attack on Greece that autumn), against Germany and Italy.

The Chiefs of Staff Committee concluded in May that if France collapsed, "we do not think we could continue the war with any chance of success" without "full economic and financial support" from the United States of America. Although its government was sympathetic to Britain's plight, American public opinion at the time overwhelmingly supported isolationism to avoid US involvement in "another European war". Reflecting this sentiment, Congress had passed the Neutrality Acts three years previously, which banned the shipment or sale of arms from the US to any combatant nation. Additionally, President Franklin D. Roosevelt was further constrained by the upcoming 1940 Presidential election, as his critics sought to portray him as being pro-war.

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