Jonathan Chait is basically correct, but I don’t think it’s accurate to say that Bernie Sanders has gotten us zero percent closer to a single-payer system for health care. Convincing almost all Democrats who have presidential ambitions to sign on for his bill is a form of progress, even if we can legitimately debate whether it alone moves the needle more or less than a rounding error from zero.

The reason I’m a little more optimistic than that is because Sanders doesn’t have to be the details guy who explains how the public is weaned off employer-based health care or convinced to pay the taxes needed to put everyone on Medicare. If he can just get the party to make that a consensus goal, he’s surely done better than zero percent.