Detroit, the punch-line to every "urban decay" joke since the 1970's, has $500 million to spend. So, what to do with it? Tear down some of the decaying, abandoned homes? Spruce up the neighborhoods that still have, you know, people living in them? Solve the crime problem (Detroit took the murder crown back from Baltimore)? The city government took a look at the array of problems facing the city and declared: "Gentlemen, what we need to solve all our problems is...light rail!" It's enough to make stones weep.