Today marks the 69th anniversary of the United States declaration of war on Japan
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The attack was on the 7th and the US declared war on Japan on the 8th
Clandestine support of Britain (for example the Neutrality Patrol) was replaced by active alliance and full participation in the European Theater. Subsequent operations by the U.S., as well as the Axis alliance, prompted Germany and Italy to declare war on the U.S. on December 11, which was reciprocated by the U.S. the same day