General Curtis LeMay saw Kennedy as a pushover and was urging him to invade Cuba and first strike the Soviets.
LeMay was easy to ignore because he was so out there. LeMay supported a first strike strategy without the provocation of something like the Missile Crisis. But ignoring Bundy, Taylor, Johnson, and others who were at that time saying the same thing as LeMay was more difficult. Kennedy managed it, and we're all here today.