The United States spends more money on public education than any other country in the world, but problems in the public schools abound. There is a struggle with variable quality among the country's more than 80,000 schools--particularly between schools in affluent suburbs and those in economically depressed inner cities. Certainly there are plenty of examples of U.S. schools and students whose performance can compete against the best in the world, but the fact remains that, in the aggregate, the U.S. can and should do better. Nearly everyone can point to problems that public schools face, and nearly everyone can offer solutions. So why haven't schools changed more? In this article, the authors' analysis leads them to suggest an answer: because they cannot. (Contains 3 notes.)