It's not every day that an American labor union gets investigated for possible ties to two of the world's most lethal terrorist organizations. But Chicago's Service Employees International Union Local 73 isn't an everyday union. Last September 24, FBI agents raided residences in Illinois, Minnesota and Michigan of more than a dozen radical activists in an effort to connect them to the Hamas (Gaza and the West Bank) and FARC (Colombia) guerrilla movements. Two of the occupants were SEIU Local 73 chief steward and executive board member Joe Iosbaker and former local board member-steward Tom Burke. Neither they nor anyone else has...