The United States of America has never declared war against Russia. A declaration of war is a formal declaration issued by a national government, indicating that a state of war exists between that nation and another.

The United States has formally declared war against foreign nations five separate times, each upon prior request by the President of the United States. Four of those five declarations came after hostilities had begun. The U.S. in its five wars has formally declared war against eleven foreign nations. The 11 countries are the UK, Mexico, Spain, Germany (WW I and WW II), Austria-Hungary, Japan, Italy, Bulgaria, Romania, and Hungary.

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