Cass Sunstein understands the limits of the regulatory state. He was head of the Office of Information and Regulatory Affairs—"the cockpit of the regulatory state," as he calls it—in 2009-12. But the Harvard Law School professor still believes passionately in the promise of good government—government that not only intends to do good but is really good at doing good. In Simpler: The Future of Government, he offers a breezy tract on how to render regulation more user-friendly and effective. . . . The author assumes, without much reflection, that government's role in protecting us from ourselves has few limits, either ethical or legal. Seldom in the book does Mr. Sunstein pause to ask if this well-meaning nudge or that benevolent order, such as those that govern our diets or our pensions, is permissible under the Constitution. Nor does he worry that government regulation might, in the long run, make people even more behaviorally quirky. If government succeeds as Mr. Sunstein believes it can at protecting us from our thoughtless dietary choices and poor investment decisions, might we not become even more infantilized? . . . [T]he regulatory state as envisioned by Mr. Sunstein is nevertheless deeply opposed to America's traditions of liberty and individual responsibility. Such regulation will chew away like a cancer at those traditions. If Mr. Sunstein's blueprint for regulation is indeed the future of government, we might, as a result, be well-regulated—but we won't be free.