So much is wrong with this analysis that it's hard to know where to begin. Let's start with the basic premise, that of a center-right American polity. To the extent that such a vague label has any real meaning, that may once have been the case. But if ours were a center-right electorate now, one imagines it might have been kinder to a center-right politician such as John McCain.
Robinson continues by suggesting that we "oscillate" between center-right and center-left, which is a little easier to buy than the far-right's ridiculous 'center-left' meme, though I think Gene is being his usual generous self. Opinion polls on the issues as well as congressional make-up in the last 50 years shows a pretty clear oscillation between center-left and center. I would suggest that the only time we swing center-right is shortly after an attack and in the early days of a war. But that's fleeting and rare.