The individual mandate, a Republican idea to subsidize private insurance companies with taxpayer money, is apparently unconstitutional, from Political Wire:
Guess what is not unconstitutional? Medicare for all. From American Prospect re-posted by Physicians for a National Health Plan:
When the Supreme Court begins its extraordinary three days of hearings on the constitutionality of the Affordable Care Act, one of the oddities will be an amicus brief challenging the act’s individual mandate from 50 doctors who support national health insurance. They point out the inconvenient truth that, contrary to the administration’s representations, the government did not need to require citizens to purchase insurance from private companies in order to meet its goals of serving the health-care needs of the populace. Congress could have enacted a single-payer law.
Since the Constitution unambiguously gives Congress the power to tax, there has never been a serious constitutional challenge to our tax-supported systems of health insurance, Medicare, and the services of the Veterans Health Administration system. In the words of the brief:
"Amici thus submit this brief for the purpose of disputing the primary tenet of the Government’s position, that Congress cannot regulate the national healthcare market effectively unless it has power to require that citizens purchase insurance from private insurance companies. On the contrary, as set forth herein, Congress has already demonstrated that it can regulate healthcare markets effectively by implementing a single payer system such as Medicare or the VHA."
Medicare For All: It's not just the right thing to do it's also the only constitutional way to provide universal healthcare.