The American Medical Association—a doctors' cartel

According to a 2007 study by McKinsey&Company, physician compensation bumps up health care spending in America by $58 billion annually,on average, because U.S. doctors make twice as much as their OECD peers. And even the poorest in specializations like radiology and surgery routinely rake in around $400,000 annually.

Doctors—and many Republicans—constantly carp about the costs of "defensive medicine" because it forces providers to perform unnecessary procedures and tests to insulate them from potential lawsuits. But excessive physician salaries contribute nearly three times more to wasteful health care spending than the $20 billion or so that defensive medicine does. "While the U.S. malpractice system is extraordinary," the study notes, "it is only a small contributor to the higher cost of health care in the United States." Meanwhile, other studies have found that doctors' salaries contribute more to soaring medical costs than the $40 billion or so that the uninsured cost in uncompensated care--the president's bete noir.