Many politicians (and many voters) duck the hard choices when it comes to Medicare reform. But what’s remarkable about the past year is that, in some ways, momentum appears to be building for real improvements to the program’s quality and sustainability. Based on a new proposal from Sens. Richard Burr (R., N.C.) and Tom Coburn (R., Okla.), the impossible seems within reach: the triumph of sound policy over interest-group politics.Today, Sens. Burr and Coburn have put forth a new Medicare reform proposal, the Seniors’ Choice Act, which combines the ideas behind the best two bipartisan plans that came out last...