As more insanely graphic Facebook message sex sessions between Rep. Anthony Weiner and Vegas blackjack dealer Lisa Weiss have been disclosed (Radar calls them "explicit and embarrassing" which is an understatement—here's a PDF), the question comes back to, "Why the hell was Weiner doing this, as a successful Congressman married to a smart and beautiful woman?" The answer is, of course, "For the thrills."

A Manhattan psychotherapist, Jonathan Alpert, tells the Daily News, "I see this a lot with high-powered people, usually men, where they're thrill-seekers. Often the risk of being caught heightens the intensity and makes it all the more thrilling." (Example: Eliot Spitzer.) And behavior expert Patrick Wanis says, "What we are seeing is a new pattern of these people who are very powerful in their position, but they seem to lack power in their personal relationships. It's a person who says, 'I'm trying to find a way to feel powerful because I have no power in my personal relationship.'" Whatever—can you really ever explain detailed messages like this (from March of this year, PDF):

Weiss: are you as passionate in the sack as u are about politics? I'm getting bored of my f*** friend
Weiner: baby you'd be crawling for the door to prevent me from f***ing you silly
Weiss: nice, just what I'm looking for. I want to bang the future mayor of nyc!
Weiner: making me h**d
Weiss: I love that you are always h**d when I talk to you
Weiner: I'm horny a lot. sorry
Weiss:me too! u have that affect on me

And that's one of the tamer excerpts! Also, why the crotch shots? Society for Sex Therapy and Research president Marta Meana gives the explanation, "The simplest theory for the behavior is that these men think the photos will serve to arouse the woman - because they, themselves, would find it arousing if that woman sent such a photo to them.... “it is likely that the act … is arousing to the sender -- sub-clinical or clinical exhibitionism. The primary intent … is to arouse themselves."