Few institutions are as loved, as loathed, and as historically important as the United States Postal Service, the subject of this landmark century-spanning social, political, and economic history. The United States Postal Service is a wondrous American creation. Seven days a week, its army of 300,000 letter carriers delivers 513 million pieces of mail, 40 percent of the world's volume. It is far more efficient than any other mail service - more than twice as efficient as the Japanese and easily outpacing the Germans and British. And the USPS has a storied history.