[lenerdenator]

Because there is no political future in doing so.

Politics is attractive to people with psychopathy. I'm not gonna say they're all that way, but a significant enough chunk of any political apparatus in the US is. If you want to have any chance of getting elected - much less having a real career - you have to play by the rules of those who see humans as means to ends and gamble that their opponents won't go as low to stop them.