In many old pictures I’ve seen of busy city streets and sports events, in addition to the standard coats and ties, men were wearing hats. This was maybe in the 30s, 40s and 50s. Somewhere, or some time, along the way, there was a shift in values and dress. The extinction of the hat in society has been attributed to the failure of John F. Kennedy to wear a hat to his inauguration (in spite of the fact that the hatters' union had given him a brand new one the day before). It is said that a hatless president set the standard, but I suspect the fashion was ready to change anyway. This might have precluded – perhaps predicted – a shift in all values.
Men lose hats, and they grow hair – the Beatniks then the hippies become the new cultural symbol. The tidy suits and ties of the ballroom eventually give way to the bare feet and open shirts (or no shirts) of that quintessential 60s cultural event, Woodstock.
When I was in the Marine Corps, we were forbidden to wear the uniform outdoors without the appropriate cover (basically our name for a hat). Certainly the mere act of wearing a hat didn't make you able to fire your weapon with more accuracy or fight with any extra portion of strength, but it was an important symbol, a basic practice of etiquette -- or what we in the south might call manners. It showed respect for the uniform, for the Corps, and for ourselves. That is the essence of what the donning of a hat meant to a gentleman 60 or 70 years ago.
Nowadays it's in fashion for young men to wear a baseball cap turned around backwards -- not to mention their pants hanging halfway down their...uh, well, you know what I mean. That is symbolic, too, I believe, of a society that has become very self-centered, where manners don't matter much anymore. It's all about "me" and you better get used to it, like it or not. I have to admit, this annoys me.
I have a hat that I wear on occasion. It's a replica of the hat Indiana Jones wore in all his movies, but less sophisticated folks confuse it for a cowboy hat. It draws comments whenever I wear it, because wearing a hat is no longer part of belonging to polite society. It is, instead, a curiosity. When I’m accused of wearing a cowboy hat, I say, “It’s not for chasing cows! This is my action-adventure hat. It’s for wild romps through jungles, and for hanging from the landing gear of a plane at 10,000 feet.” It says – I am different. Perhaps I should try something really unusual – like wearing my hat… without pants. But I won't, because I still believe that wearing both appropriately is a matter of good manners. And to me, that's still important.