What did Kennedy know about Soviet missiles during the Cuban missile crisis?

Although the article on the Cuban missile crisis at Wikipedia cites John T. Correll's article from the August 2005 issue of Air Force Magazine as saying that the Soviets had possibly only 4 operational ICBMs in October 1962, the record has changed as more and more documents come to be declassified.

According to Robert S. Norris' presentation at the Wilson Center, the Soviet Union had about 42 operational ICBMs in October 1962. Norris, Robert S., "The Cuban Missile Crisis: A Nuclear Order of Battle" (Oct. 24, 2012). Soviet Gen. Dmitri Volkogonov in 1989, however, stated that the Soviets only had 20 ICBMs ready in October 1962, and "most analysts" accept Volkogonov's estimate than the higher US estimate. Bernstein, Barton J. "Reconsidering the Perilous Cuban Missile Crisis 50 Years Later," Arms Control Today (Oct. 2012). All-in-all, Norris' full count of all available nuclear weapons concludes:

a large scale attack by the United States against the Soviet Union in October 1962 would have been with over 3500 (“fully generated”) nuclear weapons, with a combined yield of approximately 6300 megatons. This was about half of the number of warheads with U.S. strategic forces, most of which were bomber weapons for long-range bombers. The total number of nuclear weapons in the U.S. Stockpile in October 1962 was approximately 26,400 and the Soviet Union approximately 3300.

Norris at 8.

What the decision-makers knew or believed was a bit different. According to Ray S. Cline, President Kennedy was told that the United States “had at least a four-to-one advantage in ICBMs and perhaps an eight-to-one superiority in nuclear weapons capability if our powerful bomber aircraft force of that era were entered into the equation. Ray S. Cline, “Nuclear War Seemed Remote," Washington Post, February 5, 1989, p. D7. In contrast, Khrushchev believed that the US had a 17-1 ratio in nuclear fire-power. General Anatoli I. Gribkov and General William Y. Smith, Operation Anadyr: U.S. and Soviet Generals Recount the Cuban Missile Crisis (Chicago: edition q, inc.: 1994), pp. 10-11.

Tapes of Executive Committe meetings in the White House reveal that "no one in the ExComm focused on the fact that the Soviets were far behind in the strategic arms race and might well be acting [in Cuba], in part, to narrow that gap or to stop it from getting worse." Bernstein, p.2. According to Bernstein's analysis of the tapes, perhaps because a U.S. first-strike could destroy a very high number of Soviet land-based ICBMs, and make any retaliatory strike unlikely, there was usually a "heady and profoundly unrealistic sense that the crisis could be well-managed: Serious mistakes would not occur, organizations dould not make dangerous errors, and crucial orders would not be misunderstood or violated." Bernstein at 3.

Moreover, the Executive Committee's failure to try to understand the Soviet's motivation could have caused the US to push local units too hard, leading to an accidental use of nuclear weapons. Norris points out that this almost happened on October 27, when a communications intelligence officer of a Soviet Foxtrot submarine, unable to communicate with Moscow, “’became furious’ and ordered the nuclear torpedo to be assembled for battle readiness,” roaring ‘We’re going to blast them now! We will die, but we will sink them all -- we will not disgrace our Navy.” Fellow officers eventually calmed Captain Savitskiy down and the submarine surfaced. Norris at p 43, citing William Burr and Thomas S. Blanton, eds., The Submarines of October: U.S. and Soviet Naval Encounters During the Cuban Missile Crisis, National Security Archive Electronic Briefing Book No. 75, October 31, 2002, http://www.gwu.edu/~nsarchiv/nsa/cuba_mis_cri/; Svetlana Savranskaya, “New Sources on the Role of Soviet Submarines in the Cuban Missile Crisis, Journal of Strategic Studies, Vol. 28, No. 2 (2005), p. 246.