Social insurance in the United States--including the Social Security Act of 1935 and the Medicare, Medicaid, and disability insurance programs that were added later--may be the greatest triumph of American domestic policy. But true security has not been achieved. As Michael J. Graetz and Jerry L. Mashaw show in this pathbreaking book, the nation's system of social insurance is riddled with gaps, inefficiencies, and inequities. Even the most popular...