It means Harry Truman had no idea of the scum in the government.
Alan Dulles was fired by JFK for the Cuba Bay of Pigs fiasco. Then LBJ made Dulles one of the Warren Commissioners to investigate JFK's murder.
Now that we know the fix was in, Alan Dulles was an obvious pick if you wanted to hide the truth.
A Way to Prove a Conspiracy Killed JFK
The conspiracy would have never succeeded without the help of the CIA and the boys at the FBI.
Scary stuff!