Rep. Duncan Hunter, the Southern California Republican facing a rocky reelection battle after being indicted for misusing campaign funds, has upped his Islamophobic dog-whistling in recent weeks in an effort to discredit his opponent, Ammar Campa-Najjar. In a letter distributed to San Diego voters by the Hunter campaign this week, three retired Marine Corps officers wrote that Campa Najjar’s Middle Eastern heritage and relation to a Palestinian terrorist make him a national security risk.