Mann did not support the Bay of Pigs invasion, which had been planned by the CIA before Kennedy took office. He doubted the possibility of a popular uprising and, with Kennedy, opposed involvement by the US Air Force. He resigned his position at the State Department just weeks before the invasion took place in April 1961. In general, Mann felt that military action against Cuba would be too damaging for the US image. Instead, he supported economic sanctions to create suffering and dissatisfaction among the Cuban poor.