The United States Postal ServiceĀ® is an independent establishment of the Executive Branch of the United States Government. It operates in a businesslike way.
In the more than two centuries since USPSĀ® began, it has grown and changed with America. Discovering the history of the Postal Service is a journey into the history of transportation, economics, industrialization, communications, and government.
Today, the Postal Service? delivers hundreds of millions of messages each day to more than 141 million homes and businesses.
This is the story of the evolution of the Postal Service and the important role it has played in the development of the United States.
It looks like it's part of the Public sector and hence controlled by the Government. My guess is you thought it was not because of the fact that it operates as an independant establishment etc.