Very good brief history of medical insurance at National Affairs: Health Care and the Profit Motive. One quote:
When it comes to health care, liberals and conservatives often seem to be living in two different worlds. To those on the left, America's health-care system is a heartless capitalist jungle: a place where the bottom line is king, and the working poor are exploited. President Obama, for example, has accused insurance companies of holding Americans hostage in exchange for profits, and doctors of cashing in on children's sore throats by needlessly removing their tonsils. The right, meanwhile, sees American health care as an outpost of socialism: The government distorts prices and suppresses innovation, impairing the quality and affordability of care and constraining individual autonomy. Hence Republicans' call for less government involvement in insurance, and their complaints that heavy-handed Medicare rules are the source of our woes.
Simply put, liberals believe that health care is treated as a market commodity today but should not be, and conservatives think that health care is not treated as a market commodity but should be.