Cuban Missile Crisis established a naval blockade on October 22 to prevent further missiles from reaching Cuba; Oval Office tapes during the crisis revealed that Kennedy had also put the blockade in place as an attempt to provoke Soviet-backed forces in Berlin as well. The US announced it would not permit offensive weapons to be delivered to Cuba and demanded that the weapons already in Cuba be dismantled and returned to the Soviet Union. After several days of tense negotiations, an agreement was reached between US President John F. Kennedy and Khrushchev. Publicly, the Soviets would dismantle their offensive weapons in Cuba and
Cuban Missile Crisis place because its intelligence had been convinced that the Soviets would never install nuclear missiles in Cuba. EXCOMM, of which Vice President Lyndon B. Johnson was a member, quickly discussed several possible courses of action: The Joint Chiefs of Staff unanimously agreed that a full-scale attack and invasion was the only solution. They believed that the Soviets would not attempt to stop the US from conquering Cuba. Kennedy was skeptical: Kennedy concluded that attacking Cuba by air would signal the Soviets to presume "a clear line" to conquer Berlin. Kennedy also believed that US allies would think of the country