In some alternate America imagined by Pixar the health-care system could simply be reinvented.
In the real world it would be unworkable—and political suicide.
Because American health-care costs are so high, making the government assume them all would require a huge increase in taxation.
Voters in Colorado, California and Vermont, all relatively friendly territory for Democrats, rejected single-payer systems when they realised how much they cost.
The rebellion that would follow an attempt to remove jobs-based health insurance from the 55% of Americans who have it, putting medical-insurance companies out of business in the process, would make the politics of Obamacare look like a church picnic.
A better approach would be to continue changing the health-care system in small steps, frustrating though that might be.
In states that expanded Medicaid, the health-care programme for low-income Americans, the proportion of people without health insurance halved.
If Democrats can win power in states that rejected the federal government's offer to pay for Medicaid expansion, they will be able to bring down the number of uninsured further.
The markets where individuals can buy insurance should be shored up.
Finally, individuals could be offered the option to buy Medicare, paying an annual premium to the government just as they would to any other provider of health insurance.
Since Medicare has more pricing power than individual insurers do, this option ought to bring costs down eventually.
It would also provide choice for those living in the many rural areas where there is currently no competition in insurance markets.
Senators Michael Bennet and Tim Kaine have a proposal along these lines.
It is not perfect.
If premiums were not set high enough, the government’s liabilities would increase.
It would leave much of America’s frustrating health-care system unreformed.
But unlike most other versions of Medicare for all, it might actually happen.