1954 in the Vietnam War 5 April The National Security Council met again to consider U.S. intervention at Điện Biên Phủ. The Army, including Army Chief of Staff General Matthew Ridgway, was negative, stating that U.S. intervention would require 7 army divisions and heavy air support. 7 April President Eisenhower used the phrase "falling dominoes" in a press conference. This was the origin of the domino theory which postulated that if Vietnam became communist the other nearby states would soon follow. The domino theory was a prominent justification for the Vietnam War in the United States during the 1960s. 14 April Secretary of State John
US signals intelligence in the Cold War least in house arrest. A quote from "Life" magazine, generally considered friendly to Diem, suggested that a substantial number of non-communists had been arrested. This is followed by a brief note, "Yet in that same process of neutralizing opposition, Diem set the seeds for his own downfall." This followed by long redactions. Both Diem and the US Military Assistance Advisory Group (MAAG), according to the NSA history, felt the communists were going into "last gasps" in late 1959. US SIGINT support during the Vietnam War came principally from service cryptographic units, with some NSA coordination. Units still belonged to their