Federal prosecutors are seeking to revoke the U.S. citizenship of former U.S. Ambassador Manuel Rocha, the imprisoned former diplomat who served as a secret agent for Cuba dating back to the 1970s in one of the longest-running betrayals in the history of the foreign service. The U.S. Attorney's Office in Miami filed a civil denaturalization complaint Thursday that would complete the Colombian-born Rocha's fall from grace, stripping him of the citizenship he attained after moving to New York City at age 10 with his widowed mother and two siblings. Rocha, 75, was arrested in late 2023 and later sentenced to 15 years in federal prison after admitting he worked for decades as a secret agent for communist Cuba. He was secretly recorded by an undercover FBI agent praising Fidel Castro as “El Comandante” and bragging about his work for Cuba’s communist government, calling it “more than a grand slam” against the U.S.…