When I was a child, "cowboys and Indians" as Native Americans were then called, was the theme of the times. Pretty much all TV shows were Westerns, and that's what the kids wanted to emulate.

So there was this phrase going around that "Indians don't cry." Any time a kid fell and scraped a knee or something, that's what he/she would be told. The idea that Native Americans were all just naturally stoic and brave was so widespread, that's why the "crying Indian" anti-pollution PSA made such a big impact. It was a shock. It seemed out of place. Gosh, if it's serious enough to make an Indian cry....

I wonder where anybody ever came up with such a crock.