35. Operation Teardrop
In late 1944, Allied intelligence learned of the German plan to attack American cities – particularly New York City – with submarine-launched missiles. So they prepared Operation Teardrop, a US Navy operation to sink U-boats approaching the Eastern Seaboard, that were believed to be armed with missiles. Two large anti-submarine task forces were set up, and in April, 1945, Operation Teardrop was executed when word arrived that several U-boats had left Norway, bound for North America.
Of seven U-boats that approached the United States, five were sunk, and the survivors were abusively interrogated for any information about the plan to launch missiles. As it turned out, the U-boats had not been fitted out with missile-launching equipment, and the plan to attack American cities with rockets had not yet been ordered. The war ended before the Germans got around to making an attempt to carry it out.