This is the best summary I've read of the barriers to implementing significant change to our current health care system:
Sicko: Socialism in a capitalist society?:
To accomplish any meaningful reform, Americans will have to dismantle the insurance and pharma lobbies at a minimum, and begin to tackle the question of how to deliver universal health care without tying it to employment, marital status, or other qualifiers (and figure out how to put all those unemployed pharma and insurance reps to work, too). Once those lobbies have been set aside, the questions of how to implement a healthcare system which avoids the pitfalls faced by Canada, the UK and France, embraces the positives in the Cuban system, and essentially folds a socialist system into a capitalist society will have to be addressed."
[Via Kevin, MD - Medical Weblog]