As California liberals go, the Democratic Party often follows. So it’s instructive, if not surprising, that Golden State Democrats are responding to the failure of ObamaCare by embracing single-payer health care. This proves the truism that the liberal solution to every government failure is always more government.

Many on the left championed single-payer in lieu of ObamaCare’s regulations and subsidies, but in 2010 it lacked enough support among Democrats in Congress. But with premiums soaring and insurers fleeing the Affordable...