Project MINARET, the NSA’s 1967-1973 watch list, put King, Ali and two senators under warrantless surveillance. Its history, from declassified records.
Archives
VENONA: Breaking the Soviet Spy Cables, 1943–1980
How Army and NSA codebreakers read Soviet spy cables through duplicated one-time pads, and what VENONA revealed about Fuchs, the Rosenbergs and Maclean.