Chapter SixUnknown. By the end of the day, Jim wanted to beat anyone who said that word. “Unknown” had been the conclusion of everything. Was the truck driver a solo actor? A terrorist? A psycho? Or had he merely fallen asleep at the wheel? The BMW Sweep Car’s driver and his right-seat fellow agent had busted up ribs and arms but had survived. There wasn’t enough of the truck driver left to identify. First, his head and torso had been shattered by the nose of the BMW ramming through the windshield, then a fire had broken out. The spilled gas from the broken BMW finally found an ignition spark as the First Lady’s helo lifted well clear and headed to JFK to meet the waiting Air Force jet. The man who owned the truck had reported it stolen thirty-six hours earlier and had been found in a b