The U.S. and Cuba agreed to restore diplomatic ties after a half century of hostility, ending one of the world’s last Cold War standoffs and launching a realignment of the politics of the Americas.

President Barack Obama and Raúl Castro, in synchronized announcements Wednesday, said that their long-estranged countries would restart cooperation on a range of issues and reestablish an American embassy in Havana that closed in 1961 after the Cuban Revolution.

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