That the Republican Party has worked its way to a lonely and unpopular place is not news. The G.O.P.’s congressional wing has been moving rightward since the 1980s, and in the five years of the present slump they have simply picked up the pace. Once they dealt in unpopular privatization schemes, but today they have graduated to extremely unpopular shutdowns and threats of default, and those among them who hesitate are thrown to the ravening mob. Red is the color of revolution, and today the G.O.P. suffers under its own peculiar Reign of Terror, in which newly arisen extremists…