Article continues below advertisementFederal prosecutors allege that Cole Tomas Allen, a 31-year-old California man, "thought he was Rambo" and was "armed to the teeth" while attempting to assassinate President Donald Trump at the White House Correspondents' Dinner in Washington, D.C., on April 25.According to U.S. Attorney for the District of Columbia and former Fox News host Jeanine Pirro, Allen was a "brilliant" Caltech graduate and former NASA Jet Propulsion Laboratory employee who meticulously planned the attack, which he documented in a "hate-fueled" manifesto.