What [columnist E.J.] Dionne and other conventional commentators present as a right-wing coalition that comes together under “successful conservative politicians such as Ronald Reagan (and George W. Bush in his first term)” but threatens to fracture into extremism when out of power is actually something else: a fairly stable party elite that employs a rhetorical strategy to sell Americans on liberty when the GOP needs to assemble enough votes to reclaim power, but that once in command again doles out privileges to favored interests and conceals the growth of government behind moralistic and nationalistic bombast. The words may change, but the speaker remains the same.
That's Daniel McCarthy at the @TAC blog. I'll note he offers this description in the course of dismissing the notion held by some on the left that the current surge in right wing populism is somehow different than past manifestations.
I'd also say that this analysis is incredibly cynical, but I fear that it is far too accurate for that.