Since Hurricane Katrina swept ashore along the coast of the Gulf of Mexico last August, business owners in Louisiana, Mississippi and Alabama have struggled to rebuild and to reopen. A shortage of building materials has stalled reconstruction for many companies, for others a shortage of workers has stymied efforts to revive production and distribution of their goods and products. With hundreds of thousands of residents instantly scattered across the country, many of them finding new jobs where they suddenly found themselves building new lives, workers from Mexico were hired to fill the labor gap on the Gulf Coast. The influx...