The AMA has a long history of supporting government-subsidized health care, but has always drawn the line at a system of socialized medicine, ie, single-payer.

the association has balked at a key proposal from the administration:

the American Medical Association is letting Congress know that it will oppose creation of a government-sponsored insurance plan

While committed to the goal of affordable health insurance for all, the association had said in a general statement of principles that health services should be “provided through private markets, as they are currently.”

the public plan is the key element to ObamaCare.  The White House claims that they want to use it to keep insurers “honest,” but competition and sensible regulation do that.  They want to have an option to offer a loss-leader plan that will undercut the private insurers on price so that they will get forced out of the health-care sector, which will leave a single-payer plan in place by default.