Eisenhower and McCarthy
Below is some proposed language for the Ike/McCarthy subhead; I've placed it here because it contains a lot of "perhaps'es", but hopefully it's illumintating.
President Dwight D. Eisenhower due to his past close association with General Omar Bradley may have been apprised of the existence of the Venona project, the secret program within the U.S. Army Signals Intelligence Service decrypting KGB messages originating in the United States.  Eisenhower's former chief of intelligence and the first head of the CIA, General Walter Beedle Smith may have been brought in on the secret too, and the CIA began recieving some decrypted information in 1953.  There is no indication Eisenhower's Attorney General Herbert Brownell, Jr. was made aware of the highly secret information. This may explain why Eisenhower was willing to leave McCarthy barking up the wrong trees.