The answer is your beloved capitalism. But of course you will ignore this answer.
I talked to guy just yesterday that was praising Trump to high heaven, and his main point was that Trump is "incorruptible": the idea being that he can't be bought off. As opposed to all the other politicians on both sides of the isle who are totally bought off by wealthy 'super-pacs'.
I guess it hadn't occurred to him that once one is totally corrupted, and totally selfish, one technically becomes "incorruptible" by anyone else's money or agenda. He'll take the bribe money, of course, but he'll just do as he pleases regardless.