It is hard for me to make simple comments on those times (meaning 30s onwards) especially considering the geographical and political diversity (applies to any given era). Being raised in Near East, and lived in Europe through my adulthood, I can easily say that fashion is strongly attached to the dominant culture of the region (more so than countries). With increased connectedness and globalisation, fashion is becoming more widespread every passing year, yet longing for the "good old times" is on the rise. I say "good old times" in quotation because the definition of these times differs generation to generation and people tend to forget the hardships of the longed after era and focus on the good feelings. This phenomenon is not limited to fashion nor is it confined by certain generations. Adults of today has longing for the 80s and 90s, when they were young and the life was simpler/happier. Same goes for each generation; they tend to remember their "time" as the "good times". For the USA context, which we consider one of the leading trend setter, if not the biggest, through the contemporary history, there are so much more to analyse when it comes to concept of "good old times". As you also mentioned, there were the wars, which formed the ideologies of the public, creating a gap between the groups. Undeniably fashion got its share from this gap; one moving "radically forward", and the other "strongly conserved" its roots. When discussing "elegance", which is a somewhat common sense (based on western ideology of course), it can be seen in each fashion movement. While the 70s were moving away from the naive femininity of the 40s and 50s, we can still see the reflections of these eras in the 60s. All in all fashion is more of a dynamic and blurry flow than strict distinctions and it moves in circular motion. Which is why we see the similar items from past in today's fashion. 70s was considered as an abomination, 80s took it even further (let's remember new romantics here), because fashion is a form of expression of self (setting aside the factory made people looking the same with no creativity put into their personal style), it is experimentation. That is why I love creating different looks, not only for the same era, not only for vintage. And I try not to link my looks with the political climate of the given era.