I just discovered this film at my local video store. I'd never heard of it before and just happened to pick up the box. I was intrigued when I read the description. I grew up in the duck and cover era in school and would have been one of those six year olds in 1963 when this film came out so watching it brought back memories.
The film struck me as a brilliant portrayal of the emotional trauma experienced by both children and adults of that time period. I liked how it showed the various ways in which adults and children reacted to the uncertainty of the situation, with different levels of fear and anxiety, and different personality types having different responses.
The ending was shocking and unforgettable. It certainly made a statement, as we used to say. I would like to see this 1963 film play with the 1962 film La Jetee. Both films capture the angst of the era; both are unique and rarely screened films. I wish both were more well-known.