To explain that the school drills were a (clumsy) attempt to channel the growing insecurity and fear among people in the US. They pretended that an atomic attack could be handled in the same way as a fire or an accident,
Explanation:
The DUCK&COVER school drills were part of a Federal Civil Defense Administration (FCDA) program (early 50s) that was aiming to educate the public about what ordinary people could do to protect themselves. Many people were intelligent enough to realise that ducking under your table wouldn´t save you from nuclear radiation,
Dr. Strangelove by Kubrick is an interesting movie about the Cold War
