AP: Environmentalists on Friday hailed a federal judge’s ruling that allows the nation’s largest port to enforce anti-smog rules on big rigs that haul goods in and out. The case involving the Port of Los Angeles is being watched by ports around the nation that are implementing programs to reduce diesel emissions, or are considering it, but are worried that legal challenges from the trucking industry could put them in court for years. Already, the American Trucking Association says it …