What happened
General Walter Sweeney told Kennedy that an air strike could not guarantee destruction of all the missiles. This mattered because surviving weapons could still present an enormous danger. Preparations continued for the following day's announcement.
Sources for this passage: [1]Turning a decision into orders and a speech
General Walter Sweeney could not promise that an air strike would destroy every missile. As the President and advisers reviewed the coming announcement, they also debated how widely to define the shipping restrictions, when to approach the Organization of American States and how to present the case at the United Nations.
They settled on “quarantine” as the public term and an initial focus on offensive missile equipment. Rusk preferred the word partly to avoid comparison with the Soviet blockade of Berlin. Preparations for an invasion continued, including discussion of the delay between a decision, air operations and the first landings. Choosing restraint on the first day did not remove the need to prepare for the next.
Sources for this passage: [2] [1]