Page 15 on in this document describes how medicare was implemented:
You would need to expand this to the whole health care system, which is way more complex, technology oriented and labor intensive than it was 45 years ago. Cancer drugs and treatments are a new issue in health care.
And my father's experience with getting his cancer treatments with Medicare was a nightmare for his physician, who had to submit paperwork three times, and be rejected three times before his regular treatments would be re-imbursed. His physician is not accepting any more Medicare patients.
"Most health policy analysts including those who are sympathetic to the idea say moving from the current U.S. public-private hybrid health system to one fully funded by the government in one step is basically impossible. And thats making a huge assumption that it could get through Congress."
Also I trust non-partisan health care policy analysts than I would someone who has a career advocating for a specific policy. God's moving finger doesn't get inserted so much that way.