People like this have an underlying belief that anything of the political right must be motivated in some way by evil thoughts and desires. The possibility that the right could have some good ideas, or see some issue more clearly than the left, or have something useful to contribute to social or political policy, does not occur to him.
These are people who, when push came to shove, would be supporters of the one Party state, just so long as it was the right (left) Party.