Good question. It's questions like these that make me question my poor grasp of history.
I don't have an answer from personal experience as I was born after those facts.
Discussion
Maybe it's just my age bracket (Gen X) -- or, more likely, my baby boomer parents' -- but almost everything "traditional" is from the 50s. Rankin & Ross stop motion, many of the "classic" movies, the music. Maybe everyone was eager to move on from WWII and get back to life.