Not so long ago, Tunica Mississippi was a small, impoverished community along Route 61, south of Memphis, Tennessee. However, over the past fifteen years it has become home to the third largest gambling center in the United States, trailing only Las Vegas and Atlantic City. (Tunica is larger than Reno.) Initial development took advantage of a legal loophole that only allowed casinos "offshore," so they were built along a landing on the Mississippi River. This legal loophole has been reinterpreted, so casinos now operate on estuaries -- often man-made -- and what seem to be waterless ponds. Capitalizing...