There is real momentum on the American left toward moving to a single-payer, Medicare-for-all health-care system. With Republicans busy trying to pass a spectacularly unpopular bill to strangle ObamaCare and grind Medicaid down to a tiny stump, simply expanding the most generous and functional part of the welfare state to everyone makes increasing political and practical sense as a bold counter-offer. Medicare-for-all isn't going to be cheap.