Good evening, my fellow citizens. this government,
as promised, has maintained the closest surveillance
of the soviet military build-up on the island of
cuba. within the past week unmistakable
evidence has established the fact that a series
of offensive missile sites is now in preparation
on that imprisoned island. the purposes of
these bases can be none other than to provide a
nuclear strike capability against the western
hemisphere….
— president john f. kennedy, report to
the american people, october 22, 1962

president john f. kennedy reacted strongly to
the situation described in this speech primarily
because
(1) the united states feared an influx of cuban
refugees
(2) these missiles could threaten united states
oil supplies in south america
(3) the location of cuba would allow the united
states little time to respond to an attack
(4) the united states and the warsaw pact
nations had formed a military alliance