The word "asshole" is thrown around here quite often, and, IMHO, it is also a persona earnestly sought by some posters for themselves.
The Berkeley linguist Geoffrey Nunberg has written an interesting book "Ascent of the A-Word" about the history and recent increased use of the word in America. Here are the highlights of an interview he gave on NPR. The last topic is particularly applicable here.
On the origins of the word
"It's a GI's word most often used for officers, and in particular, officers who are full of themselves. The first military leader to have been called the A-word — both by his men and his superiors, by the way — is George Patton, and that makes perfect sense, particularly if you read the unexpurgated Patton, not the Patton of the movie. ... It's a word that looks up. And the A-word always does. It's a critique from below, from ground level, of somebody who's gotten above himself."
On the word entering everyday language
"By the '70s, it's been domesticated. It's been stripped of any real political significance. It's just the way in which you manifest your authenticity. There's a rejection of formality. It's the moment at which students start calling their professors 'Bob.' And the use of obscene language or profane language is an important part of that. It's the moment, for example, at which women really take up this language. They never use it as much as men do. But they use it far more in the '70s than they did in the '50s, whereas men, they've always kind of used it."
On how the word is used today
"The Internet is extraordinary. All of a sudden, if you want to pick a political fight, or a fight over chess games, or a fight over language, or a fight over bird-watching, really, you can go out there and see all these discussion groups, and people making comments on blogs and freely using this language to one another. It's an opportunity to behave like a jerk if you wake up at 3 in the morning and you feel like it."
You can listen to the complete NPR interview of Nunberg here.