The ExComm met at the State Department without the president (who was campaigning for the November congressional elections). There was still a great deal of uncertainty and vacillation, but support seemed to be coalescing around some combination of air strikes, a blockade, and diplomatic approaches
to the U.S.S.R. Former secretary of state Dean Acheson, invited by the
president, insisted on immediate air strikes to eliminate the nuclear threat and
demonstrate American resolve to the Soviets.
Excerpt taken from The Cuban Missile Crisis in American Memory: Myth vs. Reality, by Sheldon Stern