Oh...yeah, I get you. ;-) Well, it's the old "us and them" thing rearing its ugly head as usual, people imagining that all their political opponents must necessarily fit some horrible stereotype of evil or stupidity that they carry around in their minds. The Right does it. The Left does it. Insecure people of every political persuasion do it.

(a great many) Politicians attempt to provoke that sort of divisive stereotypical thinking. They figure it will gain them media attention and get them votes. And they're often right about that, unfortunately.