Following the Cuban Revolution of 1959, relations deteriorated substantially and have been marked by tension and confrontation since. The United States does not have formal diplomatic relations with Cuba and has maintained an embargo which makes it illegal for U.S. corporations to do business with Cuba. U.S. diplomatic representation in Cuba is handled by the United States Interest Section in Havana and there is a similar Cuban Interest Section in Washington D.C.; both are officially part of the respective embassies of Switzerland. The United States imposed the embargo because of the nationalization of US corporations' property during the Revolution, and has stated it will continue it so long as the Cuban government continues to refuse to move toward democratization and greater respect for human rights, hoping to see democratization and a reintroduction of capitalism of the type that took place in Eastern Europe after revolutions of 1989.
In a letter to U.S. Minister to Spain Hugh Nelson, Secretary of State John Quincy Adams described the likelihood of U.S. "annexation of Cuba" within half a century despite obstacles: "But there are laws of political as well as of physical gravitation; and if an apple severed by the tempest from its native tree cannot choose but fall to the ground, Cuba, forcibly disjoined from its own unnatural connection with Spain, and incapable of self support, can gravitate only towards the North American Union, which by the same law of nature cannot cast her off from its bosom." In 1854 a secret proposal known