Did the British plant a bomb at the World's Fair in 1940?

It was the surprise attack on Pearl Harbor that finally pushed the United States to enter World War II, but a little-known bombing at the World's Fair in New York City nearly a year-and-a-half before - which resulted in the deaths of two NYPD officers - may have laid the groundwork.

It has been suggested that the bomb may have been planted by a British spy, in an attempt to gain American support for the British cause.

NYPD Lt. Bernard Whalen has studied the World's Fair bombing extensively for two books he wrote on the history of New York's finest.

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