CNN  —  Early in his presidency, in May 1977, then-President Jimmy Carter gave a commencement speech at the University of Notre Dame that outlined a new approach to America’s role in the world: Carter said human rights should be a “fundamental tenet of our foreign policy.” This was a sharp break from the foreign policy practiced by Carter’s predecessor, President Richard Nixon, who, during the Vietnam War, stepped up the secret American bombing s of Vietnam’s neighbors Cambodia and Laos,