Over the past quarter century, U.S. taxpayers have pumped more than $100 billion in subsidies into the nation's urban mass transit systems. That massive taxpayer investment has paid for urban public transportation systems that fewer and fewer Americans are using. Incredibly, mass transit ridership is lower today--not only as a percentage of commuter trips taken but also in absolute numbers of riders-- than it was in the early 1960s. Despite the low and declining use of bus and rail systems, federal grants for urban transit now appear to be as popular as ever: bills before both houses of Congress would...