That was the feel-good non-starter that I got taught in school (in the US, in the 1980s). We learned it, class-by-class, from then-old film reels projected on a relatively big screen in a relatively small classroom.

So sure, why not?

[1]: https://footagefarm.com/reel-details/nuclear/atomic-bomb/duc... is an example of a tired old film, and I distinctly recall it being shown to my class in a public school sometime in the 1980s. Even though big parts of it were already rather outdated by that time.

Even though neither I nor my classmates were never alive and aware at a time when Civil Defense was a thing.

(Thattaboy, Tony.)