I would like to see some citations please. America has been a conservative, center-right nation since its founding.
And the Democratic party is to the right of center-right. So what's your point? The Democratic party is further right now than it has been at any time since the 1930s. The populace has mostly drifted left. The Tea Party, on the other hand, is the furthest extremist right party the US has had in the past century.