Pictured are warships during the 1898 Spanish-American War, after which the U.S. acquired from Spain new territories thousands of miles from the mainland. Bettmann/Getty Images As the U.S. celebrates its 250th anniversary, millions of Americans who live outside the 50 states are excluded from full participation in its democracy. Roughly 3.6 million residents of U.S. territories – including Puerto Rico, Guam, American Samoa, the Northern Mariana Islands and the U.S. Virgin Islands – have no senat