Experts debate theory that hijacker was exposed By Steve Fainaru and Ceci Connolly THE WASHINGTON POST March 29 — In January, outside of formal channels, an FBI official asked biodefense experts at Johns Hopkins University to examine a curious lead in the federal government’s investigation into last fall’s anthrax attacks.THE EXPERTS were to evaluate the diagnosis of a Fort Lauderdale, Fla., emergency room physician who had treated one of the Sept. 11 hijackers last June. The physician, Christos Tsonas, initially thought the man had a minor infection, but after the wave of bioterrorist attacks he told the FBI that, in...