The “ten year war” of the title refers to the decade from U.S. President Barack Obama’s election in 2008 to the defeat of the House Republican majority in 2018, in which no political issue was more decisive than the Affordable Care Act, the most important piece of legislation in the country in half a century. Cohn recognizes that the law is “highly flawed, distressingly compromised, [and] woefully incomplete,” but he nonetheless credits the act with representing a major step toward establishing affordable health care as a universal right, as it is in every other developed country. Unrelenting Republican determination to repeal the law and replace it with an undefined alternative has prevented legislators from correcting the inevitable defects in a massive new government program, leaving the law weaker than it should be. Cohn traces the debate over the ACA as it unfolded in think tanks, lobbyist offices, legislative committees, and the Oval Office with impressive clarity and in an engaging, highly readable narrative that makes arcane issues accessible. His own bias in favor of universal coverage is explicit, but he treats fairly the philosophical and economic arguments of the opposing view. This valuable history will help inform the continuing battle for an efficient, equitable, and affordable U.S. health-care system.