If you look at other industrialized countries, they have single-payer and they spend way less than we do. Make your own conclusions.
The conclusion is easy to draw. The US Federal Government covers 1/3 of the population and spends 300% more per capita than the rest of the OECD. The spendthrift forces Americans to purchase another health insurance policy in the private market. The citizens who can't afford to buy healthcare twice are now legally required to buy health insurance under threat of impoverishment.
We have the budget in place. Either make Medicare/Medicaid available to everyone without conscripting more funds or shut up. We're already buying the stuff liberals want, but they elect peerless halfwits who can't deliver a ham sandwich for less than $20.
The world is just twiddling its thumbs in a QE holding pattern, waiting on the lowly, stubborn Donkeys to get their act together. The Donkeys are demanding another trillion dollars in tax revenue before they budge. America needs to show them a picture of the glue factory.
And this is just public healthcare. It will probably take another 30 years to make the stubborn Donkeys move on Social Security reform, and another 30 years for Welfare conversion to EITC, and so forth.