A reader passes along an interesting WSJ story on some businesses' anxiety about a potential "crackdown" on "undocumented workers." An interesting bit of information on the number of construction workers who are thought to be "undocumented":

In the $1.2 trillion construction industry, at least one-third of the work force is undocumented, according to an estimate by the Bureau of Labor Statistics. Industry experts believe the actual figure is much higher: Last year alone, nearly half of new construction workers were Hispanics who had arrived in the U.S. since 2000.