"And, indeed, as recently as 1988 one could have witnessed moderate Democrat Joe Lieberman successfully challenging incumbent liberal Republican Senator Lowell Weicker with the support of, among others, William F Buckley, Jr. "But it turns out that Lieberman vs Weicker was something of a dying gasp of a political order that was rendered obsolete by the civil rights revolution. Twenty years later we find ourselves several congresses into a brave new world in which every single Democratic Party legislator is to the left of every single Republican Party legislator. In terms of partisan politics, in other words, we’ve become a normal country. But as Linz observed, the “normal” outcome for a country with our political institutions and ideologically sorted parties is constitutional crisis and a collapse into dictatorship. "So far it hasn’t happened here. The 1998-99 effort to impeach Bill Clinton was sufficiently unpopular that moderate Republicans wouldn’t vote for it. A