The extreme right and the extreme left are merely flip sides of the same coin. They are people who know what's best for everybody else, and if they don't comply, they will have it crammed down their throats if enough power can be gained.
"Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive. It may be better to live under live robber barons than under omnipotent moral busibodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good, will torment us without end, for they do so with the approval of their own conscience." ~ C.S. Lewis