If you were to vacation in Los Angeles this summer and drive west along Wilshire Boulevard, say, from Beverly Hills to Santa Monica, you would pass through some of the most valuable real estate on the planet. The drive would take you through the wealthy neighborhoods of Westwood and Brentwood, and the even wealthier enclaves of Holmby Hills and Bel Air would be just a few blocks off your route. At no point along your way would you be within a mile or more of even a single home worth less than a million dollars. You would also pass, very...