The thirteen days marking the most dangerous period of the Cuban missile crisis begin. President Kennedy and principal foreign policy and national defense officials are briefed on the U-2 findings. Discussions begin on how to respond to the challenge. Two principal courses are offered: an air strike and invasion, or a naval quarantine with the threat of further military action. To avoid arousing public concern, the president maintained his official schedule, meeting periodically with advisors to discuss the status of events in Cuba and possible strategies.