American U2 flights take pictures over Cuba, Later, those photos would be analyzed and it would be discovered that the USSR had been building missile sites
Period: to
Cuban Missile Crisis
Missile Sites confirmed
Kennedy notified
Kennedy notifies the nation
Castro urges Khrushchev to nuke the US
Khrushchev offers to remove the missiles
Black Saturday: American U2 shot down over Cuba. Khrushchev sends Kennedy a second letter demanding harsher terms.