Without the intelligence that revealed the existence of the missiles during the Cuban Missile Crisis, persuading the world of the Soviet Union's secret actions would have been much more difficult. The U.S. would have had to rely on other methods to try to prove that the missiles existed and that the Soviet Union was engaged in aggressive behavior. Some possible methods that the U.S. might have used include:
Satellite imagery: The U.S. had access to sophisticated satellite technology that could have been used to photograph the missile sites in Cuba. However, the resolution of the images was not as high as it is today, and it would have been difficult to definitively prove the existence of the missiles without ground verification.
Human intelligence: The U.S. could have attempted to send spies into Cuba to gather information about the missile sites. This would have been risky, however, as Cuba was heavily guarded and the Soviet Union was known for its effective counterintelligence measures.
Diplomatic pressure: The U.S. could have attempted to pressure other countries to take a stance against the Soviet Union based on political or economic interests. However, this approach may not have been effective in convincing other countries to take a strong stance against the Soviet Union without concrete evidence of their actions.
Overall, without the intelligence that revealed the existence of the missiles, persuading the world of the Soviet Union's secret actions would have been much more challenging and may have required the use of other methods to prove their aggressive behavior.