On October 22, 1962, President Kennedy announced in a nationwide television broadcast to the American people the presence of nuclear missiles in Cuba. He also warned Soviet Premier Nikita Khrushchev that using the missiles against any country in the Western Hemisphere would be equivalent to an attack against the United States, and which would force the U.S. Armed Forces to retaliate against the Soviet Union. President Kennedy then called on the Soviet Union to remove the missiles. He also announced a naval “quarantine” of offensive weapons into Cuba, i.e. the U.S. Navy would seize offensive weapons before they reached the island. The quarantine was to prevent Soviet ships from bringing more nuclear missiles to Cuba. President Kennedy chose to use the word “quarantine” instead of “naval blockade” since the latter was an act of war under international law. Some 300 U.S. Navy ships were tasked to enforce the quarantine. The United States Armed Forces worldwide (except in Europe) were placed on a higher state of readiness.
On October 23, 1962 the United States gained the approval of the Organization of American States (OAS), which voted 20–0 (with Cuba not participating) to endorse the naval quarantine; a number of OAS member countries pledged to provide soldiers, ships, logistical support, and naval bases for the quarantine.
The Soviets reacted strongly against the naval quarantine, with Premier Khrushchev, on October 24, calling it a violation of international law and declaring that the blockade was an “act of aggression” that would lead to war and that Russian warships would ignore the American “piracy”. The Soviet leader declared that the “armaments…in Cuba, regardless of classification…are solely for defensive purposes…to secure Cuba against the attack of an aggressor.” Escorted by submarines, Soviet freighters bound for Cuba appeared determined to ignore the quarantine. However, Premier Khrushchev soon ordered the cargo ships to change course or turn back. The next day, Adlai Stevenson, U.S Ambassador to the United Nations, presented the U-2 aerial photographic evidence of the nuclear missiles to the UN Security Council. Stevenson asked Valerian Zorin, the Soviet Ambassador to the UN, about the missiles, but the latter refused to confirm or deny their deployment.
(Taken from Cuban Missile Crisis – Wars of the 20th Century – Volume 2)
In August 1962, U.S. reconnaissance flights over Cuba detected the presence of powerful Soviet aircraft: 39 MiG-21 fighter aircraft and 22 nuclear weapons-capable Ilyushin Il-28 light bombers. More disturbing was the discovery of the S-75 Dvina surface-to-air missile batteries, which were known to be contingent to the deployment of nuclear missiles. By late August, the U.S. government and Congress had raised the possibility that the Soviets were introducing nuclear missiles in Cuba.
By mid-September, the nuclear missiles had reached Cuba by Soviet vessels that also carried regular cargoes of conventional weapons. About 40,000 Soviet soldiers posing as tourists also arrived to form part of Cuba’s defense for the missiles and against a U.S. invasion. By October 1962, the Soviet Armed Forces in Cuba possessed 1,300 artillery pieces, 700 regular anti-aircraft guns, 350 tanks, and 150 planes.
The process of transporting the missiles overland from Cuban ports to their designated launching sites required using very large trucks, which consequently were spotted by the local residents because the oversized transports, with their loads of canvas-draped long cylindrical objects, had great difficulty maneuvering through Cuban roads. Reports of these sightings soon reached the Cuban exiles in Miami, and through them, the U.S. government.
The weight of circumstantial evidence reaching the United States prompted the Kennedy administration to increase air reconnaissance missions over Cuba. On October 14, 1962, a U-2 spy plane took hundreds of photographs which, after being filtered and analyzed by the CIA, revealed the construction in San Cristobal, Pinar del Rio Province (Map 23) of a Soviet nuclear missile site for MRBMs that were capable of striking within a range of 2,000 kilometers, including Washington, D.C. and the whole southeastern United States.
On October 16, 1962, President Kennedy was informed of the findings; he formed a panel consisting of members of the National Security Council, or NSC (the President, Vice-President, Secretary of State, Secretary of Defense, Chairman of the U.S. Armed Forces Joint Chiefs of Staff, among others) and advisers. This panel would later (October 22, 1962) be officially established as the ExComm (Executive Committee) of the NSC and tasked to formulate the United States’ appropriate response to the Soviet missile deployment in Cuba.
The military members of ExComm believed that the missiles changed the strategic balance of power between the United States and the Soviet Union, but President Kennedy and Defense Secretary Robert McNamara disagreed, saying that the Russians already possessed ICBMS and nuclear submarines that could target the United States, with or without the missiles in Cuba. However, all ExComm members agreed that the missiles changed the political balance and would damage the credibility of President Kennedy with the American people, his western allies, and the international community, as it would appear that the United States was incapable of standing up to the Soviet Union.
The military members of ExComm advocated a military solution, including air strikes to destroy the missiles before they became ready, and a full-scale invasion of Cuba. President Kennedy demurred, believing that American military action might provoke the Soviets to invade West Berlin or destroy the American Jupiter missiles in Turkey; in turn, NATO would be forced to respond, thereby escalating the conflict into a full-blown war. West Berlin, administered jointly by the United States, Britain, and France, was located within the territory of East Germany and long desired by the Soviet and East German governments to be merged with East Berlin, East Germany’s capital.
ExComm unanimously agreed that the missiles must be removed. President Kennedy authorized the military to prepare for war, although he wanted to explore non-combat options first. The armed forces were placed on alert status, with 250,000 troops transferred to Florida and Georgia; three battalions were sent to Guantanamo Bay Naval Base in Cuba to reinforce the existing forces there. In the following days, more U-2 flights, including low-level aerial reconnaissance, showed that three other missile sites were being established and nearly completed, two of which were for IRBMs which, with a flight radius of 4,800 kilometers, could target all of the continental United States, except Alaska, Oregon and Washington states.
On October 18, 1962, ExComm decided to pursue one of two options: an air strike or a naval blockade. The U.S. Air Force could not guarantee that American air strikes would destroy all the missiles, however, thereby pushing most of the ExComm members to go for a naval blockade, which also was President Kennedy’s first option.
Without revealing that he was aware of the missile deployments, President Kennedy met with Soviet Foreign Minister Andrei Gromyko, who assured the American president that only Soviet defensive weapons were being delivered to Cuba. Many Soviet pronouncements leading up to the delivery of the missiles had been aimed to assure the United States that no Soviet offensive weapons would reach Cuba. Fidel Castro, without mentioning the missiles, declared that Cuba had the right to defend itself from foreign, i.e. American, aggression.