WASHINGTON: Since Mr Obama took office, the rate of threats against the president has increased 400 per cent from the 3,000 a year or so under President George W. Bush, according to Ronald Kessler, author of In the President's Secret Service.Some threats to Mr Obama, whose Secret Service codename is Renegade, have been publicised, including an alleged plot by white supremacists in Tennessee late last year to rob a gun store, shoot 88 black people, decapitate another 14 and then assassinate the first black president in American history.LINK