Islamic extremists have been moving supplies and new recruits from Iran into Iraq, say Iraqi Kurdish and Western officials, though it’s unclear whether Tehran is covertly backing them or whether militants are simply taking advantage of the porous border.Iranian involvement with extremist groups in the Iraqi insurgency would be potentially explosive, especially given the history of U.S.-Iranian animosity. Defense Secretary Donald H. Rumsfeld said recently Iran was engaged in “a lot of meddling” in Iraq but gave no details.Full Story