In July 1964, President Johnson ordered a review of the risk of another Cuban Missile Crisis happening and for an outline of the alternative courses of action that would be available.
In National Security Action Memorandum No. 311 (NSAM 311), President Johnson ordered Secretary of State Dean Rusk, Secretary of Defense Robert McNamara, and Director of Central Intelligence John McCone to review the prospect of a repeat of the Cuban Missile Crisis and to outline the various alternatives that would be available if it happened.
This history of the National Security Council under presidents Kennedy and Johnson was written by the Executive Director of the NSC under both presidents, Bromley Smith. It traces not just the mechanics of the NSC during the period but also how it was used to tackle specific topics.
Here are the results of a Mandatory Review request I filed with the LBJ Library in 2010 for declassifying closed sections of LBJ’s so-called “X” file on Richard Nixon, the bombing halt, and the 1968 election.