President Bush has signed an executive order requiring contractors and others who do business with the federal government to make sure their employees can legally work in the United States. Mr. Bush signed the order Friday and the White House announced the order Monday. Homeland Security Secretary Michael Chertoff and Commerce Secretary Carlos Gutierrez planned an afternoon news conference to discuss the order and other ways the administration has stepped up its crackdown on illegal immigration. The order says federal departments and agencies must require contractors to use an electronic system to verify that the workers are eligible to work...