The parties simply re-adjust their policy mixes until they appeal to about half the electorate. You say that as though the merits of various policies are equal

The parties simply re-adjust their policy mixes until they appeal to about half the electorate. You say that as though the merits of various policies are equal along an infinite continuum. Sure, the parties will readjust. Apparently, we're going to readjust after this election to debt-to-GDP ratios that collapsed Greece, immigration policies that will create a race to the bottom culturally, and a continued emphasis on government power over Liberty. We have decided as a nation to compromise with our worst influences.