Can some explain to me what this comment by some hardcore libertarian on another site means?

"It seems to me that any political system that has only two parties operating on a narrow ideological spectrum will tend to dovetail rather than to polarize. Everyone knows that politicians lie. Every four years you choose the best liar and are then surprised that you've been deceived when your politician doesn't do what he promised? Politics in America is a mug's game - because the electorate are so ill informed and jingoistic to begin with, it is easy to stampede them into choices made on the basis of fear and hatred (which is a manifestation of fear). Scratch either a Republican or a Democrat and you will find a politician. Scratch a Tea Party adherent and you'll get bile instead of blood - and a shotgun shoved in your face."