The 2 big disagreements between the 2020 Democratic candidates on Medicare-for-all

The Democrats running for president in 2020, while sharing a general goal of “expanding health coverage,” have two fundamental disagreements about health care.

One is on the policy: Would the best insurance system be one fully funded by the federal government? The Democrats who support Sen. Bernie Sanders’s Medicare-for-all bill are saying it is, while other candidates prefer to build more gradually on the public-private system we have now or openly running against the idea of single-payer.

The other debate is over strategy: Even if Democrats are lucky enough to...