On rare occasions in American history, Congress enacts a measure so astute, so far-reaching, so revolutionary, it enters the language as a metaphor. The Marshall Plan comes to mind, as does the Civil Rights Act. But perhaps none resonates in the American imagination like the G.I. Bill. In a brilliant addition to Oxford's acclaimed Pivotal Moments in American History series, historians Glenn C. Altschuler and Stuart M. Blumin offer a compelling...