The Cuban missile crisis. How is the evidence interpreted today.?

You are incorrect about spies on the ground. The CIA had assets on the ground in Cuba who reported unusual activities in Cuba in August, 1962. U2 flights were suspended on August 29th because of the deployment od surface-to-air missiles. After the CIA assets reported the probability of nuclear weapons in Cuba, the U2 flights were resumed, The reason the flights were resumed was to gather photographic evidence to display to the public without disclosing that CIA spies found the evidence. Read the Smithsonian article in the link below.

The evidence is the evidence, there is no new device capable of discerning items which do not show i.e. whether a warhead actually was nuclear or not.

I was 11 years old during the Cuban Missile Crisis and we were all scared. The USSR installed medium range ICBMs In Cuba that were nuclear tipped and we were in range and Columbus, Ohio had the Defense Logistics Agency which was a target. Walter Cronkite and John F. Kennedy were on TV and Walter Cronkite was scared but JFK was not scared.