The History Channel is running a show about the Cuban Missile Crisis, from almost 40 years ago today. This occurred when JFK found out that the Nikita Khrushchev's Russians had installed nuclear missiles in Cuba.
Many options for a response were considered, including a land invasion.
At that time, unknown to US intelligence, the Russians had tactical nuclear weapons in Cuba (including nuclear torpedos). These could have been used to vaporize many if not all of our personnel involved in the invasion. According to Khrushchev's son Sergei, these weapons were likely to have been used in case of an invasion.
Does this sound familiar?