On the dusty grounds of Lone Star Army Ammunition Plant in Texarkana, Tex., the recreational vehicles and mobile homes are arriving at a rate of 100 a day before being shipped out to the fringes of Hurricane Katrina's disaster zone. Those trailers, among 300,000 to be purchased with nearly $5 billion of federal money, have become a focal point of criticism of the Bush administration's early rebuilding efforts. Some conservatives blanch at the cost. And many critics fret that mobile homes will hardly protect their residents from the next storm. But most of all, housing experts -- conservatives and liberals...