Keep in mind I'm paraphrasing this from memory but:
"In my main line of work, we breed fruit flies. We noticed that the some of the more aggressive males would fight over a bit of land, plant, whatever, to court females. We wondered what would happen if we only let the aggressive flies breed, and within 10 generations we had flies that were like Hercules (fruit flies breed very fast which is why they are used to study genetics and evolution). We then reintroduced them back to the more natural population of flies. What ended up happening was; while the aggressive flies were busy fighting, the non-aggressive males were hanging out with the females and making babies. The aggression was quickly bred out and after a couple of generations it went back to initial levels. We often hear the phase 'survival of the fittest' in this field of study, but just a reminder that it doesn't always mean what you think it means."
I thought that was an interesting aside that you might enjoy. 
A lot of it is new and depends on culture. It used to be the height of manliness to wear a silk cravat and a powdered wig in western cultured.
I point to the shift happening around the industrial revolution. I think that screwed with a lot of peoples' perceptions of themselves, since it was effectively a process of domesticating people.
Now people are entirely domesticated and detached from their labor, so we've had to invent new personas for people to adopt. The brave strong manly individualist aggressive guy with guns is someone trying to emulate what he thought American homesteaders were like in the early 19th century, pre-industrial revolution. That's how I see it at least. Also yes it's consumerist inventions so companies can sell two versions of the same product: a pink one covered in glitter and a "tactical" one in camo.