The Department of Homeland Security issued its first anti-terror directive for the nation’s commuter rail and subway systems yesterday, calling for wide-ranging precautions including checks of unattended bags, bombproof trash receptacles and the use of explosive-sniffing dogs. Local rail operators, including Metro, MARC and Virginia Railway Express, said they believe they are already substantially in compliance with the rules, though they could not be sure. The regulations are to go into effect on Sunday, but operators said they had not been issued copies of the requirements. Some in the industry questioned whether the transit systems have enough money to fully comply. Full Story