... Sanders’s proposal actually scraps Medicare’s operating model, which mimics the private sector’s insurance-company-based structure, including the use of private insurers for administrative tasks. BernieCare, by contrast, would eliminate the private sector’s role in insurance provision. In fact, Sanders seeks to discard the current patchwork of government and private options: Medicare for the elderly, Medicaid for the poor, employer-provided insurance for the better-off and ACA policies for those who fall through the cracks.

Sanders’s legislation would instead place everyone, except beneficiaries of Veterans Affairs and the Indian Health Service, into one plan. Proposed benefits are generous, covering services ranging from doctor and hospital to mental health and substance abuse care. With the exception of some minor cost-sharing for prescriptions, the plan eschews traditional ways of discouraging services overconsumption, such as deductibles and coinsurance.

But BernieCare faces at least two significant challenges: selling the legislation to voters and creating a program that fairly and efficiently distributes medical services.

The history of health-care politics, especially the two most significant legislative rewrites — Medicare and the ACA — illustrate these challenges and reveal why BernieCare is unlikely to succeed. Medicare garnered much broader political support than the ACA because voters and politicians believed it would complement, rather than undermine, existing health-care arrangements. By contrast, ACA opponents have spent almost 10 years arguing that the program destabilizes the entire health insurance system — a weapon that will be wielded even more effectively against BernieCare. ...