“Missile gap” is a phrase used during the Cold War, referring to the theory that the US lagged behind the Soviet Union in terms of its ballistic missile defenses.
The US and the USSR were engaged in a high-stakes arms race by the 1950s. That race intensified after the Soviets successfully launched Sputnik I in 1957. Sputnik was the world’s first man-made satellite. On its own, it did not pose any threat to the US or other nations. However, Sputnik was proof positive that the USSR possessed missile technology capable of launching an object into orbit – something which the US did not yet possess.
With the launch of Sputnik, the US government became convinced that the Soviet Union had the capability to threaten the continental United States with ballistic missiles. In the same year, a presidentially-commissioned report on US nuclear policies was commissioned, which drew some very pessimistic conclusions about America’s missile readiness compared to that of the Soviet Union. The s-called Gaither Report claimed that the Soviet Union could have a “significant” inter-continental missile capability within two years and that it might be able to strike at America’s Strategic Air Command’s bomber fleet. The report was classified as top secret but some of its contents were leaked to the media, feeding the public perception that America faced an existential threat from Soviet missiles.
President John F Kennedy is closely associated with the concept of the missile gap; JFK talked about the need for the US to increase its ballistic missile system from 1958 onwards, when he was running for re-election to the Senate. Kennedy also critiqued President Dwight D Eisenhower as being supposedly lax on missile defense.
Once he was in office, JFK was informed that in fact, there was no missile lag; the US was believed to be on a par with, or even superior to, the USSR as far as ballistic missile technology went. (The intelligence community had revised its earlier, overblown estimates of Russia’s capabilities by the time JFK came into office.) JFK did not publicly refute what he had said, but he joked about his mistake behind closed doors, telling his advisors that “a patriotic and misguided man” had “put that myth around.”
American anxiety about the missile gap reached a peak in 1962 with the Cuban missile crisis, an event lasted just under two weeks but resonated in the public imagination for far longer. On October 16, 1962, the president was informed that the Soviet Union was building missile launch sites in Cuba. (This came in response to the Bay of Pigs invasion and to the American decision to install its own missile launch sites in Italy and in Turkey.) In response, JFK imposed a naval blockade around Cuba which remained in place until November 20, when the US confirmed that all of the ballistic missile systems had been taken apart.
Behind the scenes, during those tumultuous two weeks, the US and the USSR reached a private agreement under which the USSR would dismantle its Cuban missile sites in return for the US doing the same to its own sites in Turkey.