Among the strange developments of this session is the desperate efforts of moderate Republicans in the House to play defense, trying to hold off opposition from the tea party types. This includes some of the chamber’s best members. How do you play defense? You sign on as a cosponsor for every nutty, far-out piece of legislation and join every organization that plays to the party’s base–immigration bills, gun bills, tea party caucuses, abortion bills, Tenth Amendment pipe dreams. Members who are trying to advance the ball feel compelled (and with good reason) to establish their conservative bona fides. I don’t think that there is a Republican in either House–other than the far right fringe–that isn’t worried about getting primaried.