If we can get to universal health care, the role of private insurance companies would be greatly diminished. Insurers adjust premiums to risk, but with universal care, all are in the pool so that role is gone.
Another major role has been for insurers to approve medical decisions.
This is an unacceptable conflict of interest, as their preference is to deny, deny, deny. What is left is the paperwork, and with so many insurers, each with its own method, the resulting cost and inconvenience is wasteful.
It is important to recognize that we citizens pay all medical expenses -- by premiums; direct payments to providers; for malpractice insurance; for the costs of care for indigents and the uninsured; and through taxes. If the feds increase the debt because of shortfalls in taxes, that is our debt. There is no fairy godmother.
By going to a single-payer system like most other developed countries, we can approach their much lower cost. If the total cost can be cut by paying more of it in taxes, that would be a good deal. Also, getting all insured will be a snap with a tax.
We are half "socialized" already, what with the federal government managing Medicare, Medicaid and veterans' care, and doing a pretty good job of it. Why, then, are we all so concerned about going the rest of the way? I have been on Medicare for more than 20 years, and would not trade that for any private insurer.
Getting agreement on a single payer will be difficult. One way to get there eventually is to include a Medicare-like option to compete with existing insurers. This is a must.