Historically, health insurance has been regulated by the states, consistent with the McCarran-Ferguson Act. Details for what health insurance could be sold were up to the states, with a variety of laws and regulations. Model acts and regulations promulgated by the National Association of Insurance Commissioners (NAIC) provide some degree of uniformity state to state. These models do not have the force of law and have no effect unless they are adopted by a state. They are, however, used as guides by most states, and some states adopt them with little or no change.
In 1935 the decision was made by the Roosevelt Administration not to include a large-scale health insurance program as part of the new Social Security program. The problem was not an attack by any organized opposition, such as the opposition from the American Medical Association that derailed Truman's proposals in 1949. Instead, there was a lack of active popular, congressional, or interest group support. Roosevelt's strategy was to wait for a demand and a program to materialize, and then if he thought it popular enough to throw his support behind it. His Committee on Economic Security (CES) deliberately limited the health segment of Social Security to the expansion of medical care and facilities. It considered unemployment insurance to be the major priority. Roosevelt assured the medical community that medicine would be kept out of politics. Jaap Kooijman says he succeeded in "pacifying the opponents without discouraging the reformers." The right moment never came for him to reintroduce the topic.
Employer-sponsored health insurance is paid for by businesses on behalf of their employees as part of an employee benefit package. Most private (non-government) health coverage in the US is employment-based. Nearly all large employers in America offer group health insurance to their employees. The typical large-employer PPO plan is typically more generous than either Medicare or the Federal Employees Health Benefits Program Standard Option.
In addition to medical expense insurance, "health insurance" may also refer to insurance covering disability or long-term nursing or custodial care needs. Different health insurance provides different levels of financial protection and the scope of coverage can vary widely, with more than 40% of insured individuals reporting that their plans do not adequately meet their needs as of 2007.