We thought that House Budget Committee Chairman Paul Ryan’s attempt to reform Medicare had struck a fatal blow against the “third rail” mentality in Washington — that cultural defect whereby politicians run in terror from anything new, no matter how necessary it is. Unfortunately, we are being proven wrong — not by voters, and not by Democrats’ “Mediscare” tactics, but by Republicans who are going wobbly, distancing themselves from Ryan in search of a political advantage. Given the dire need for Medicare reform, these Republicans are imperiling the nation’s future, to say nothing of the GOP’s political fortunes. Former Republican House Speaker Newt Gingrich provided the first sound bite for Democrats’ 2012 ads when he denounced Ryan’s plan as “radical” and “right-wing social engineering.” From the opposite end of the spectrum, Sen. Rand Paul, R-Ky., criticized Ryan’s plan for spending too much, even though it may be Medicare’s only hope for long-term sustainability. Then came Sen. Scott Brown, R-Mass., a rising moderate star in the GOP. Brown wrote in a Politico op-ed that he will vote “no” on Ryan’s plan, and instead wants a plan that “[protects] those who have been counting on the current system their entire adult lives” and that gradually phases in changes “to give our future seniors enough years to adjust to the ‘new normal.’ ”