Key Difference: United States (U.S.) and United States of America (U.S.A.), both refer to a federal republic that consists of fifty states and a federal district. Therefore, there is no difference between the two.

Some people may think that U.S. and U.S.A. both refer to two different nations. However, both refer to the same country.

U.S. and U.S.A, refer to a North American Republic. Full name of the country is United States of America. The country is bounded on the east by the Atlantic Ocean and Pacific Ocean lies in the west of the country. It occupies a territory of 9,522,0572 square km. The altitude and longitude for the country are 40.4230° N, 98.7372° W repectively.

Forty-eight of the states of the country are situated in a single region between Canada and Mexico. The other two are located in Alaska and the archipelago of Hawaii. It shares the main four time zones with Canada ( Eastern Time , Central Time, Mountain Time and Pacific Time ).

The country was first settled by the English in the 1600s. It remained a British colony until July 4, 1776. Later, the colonies declared independence, and the independence was firstly stated in a document that was written by Thomas Jefferson of Kingdom of Great Britain and thus, the foundation of United States of America was laid. Today, all states comprising the U.S.A, have their own constitution, legislature, judiciary, executive branch and capital city. However, they all share sovereignty with the central federal government.

A brief on U.S. military operations

Is same as

A brief on U.S.A. military operations

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