What sparked the cuban missle crisis

In October 1962, American ships blocked Soviet ships carrying missiles from going into Cuba. The Soviets and Cubans agreed to take away the missiles if America promised not to attack Cuba. During the Cuban Missile Crisis, the Kennedy administration secretly agreed to remove the Jupiter missiles from Turkey in exchange for the withdrawal of all Russian nuclear weapons from Cuba. However, it is not decided if anyone "won". The USSR lost China's support over it.