I want to know the answer to the following question:
When did Dien Bien Phu fall to the communists?
All the background I'm provided with is that "When the French fortress of Dien Bien Phu fell to the Vietnamese Communists in May 1954, Eisenhower refused to intervene despite urgings from the Chairman of the Joint Chiefs, the Vice President and the head of NCS.". Is that enough to answer the question?