Cole Allen thought he was “Rambo” and armed himself “to the teeth” to try to kill President Trump at the White House Correspondents’ Dinner, DC’s top law-enforcement official revealed Sunday. Jeanine Pirro, US attorney for the District of Columbia, stressed it wasn’t friendly fire but Allen, 31, who shot a Secret Service officer when he stormed the Washington Hilton last month, and that she is confident her team can prove the “brilliant Caltech grad intended to kill Trump. “Clearly, the president is a target. And make no mistake, it is not just the manifesto. It is his actions,” Pirro told CNN’s “State of the Union,” referring to Allen’s alleged hate-fueled missive in which the mechanical-engineering grad and former NASA intern outlined his violent plans while calling himself the “Friendly Federal Assassin’ Allen.” Cole Allen smugly grins in his hotel room before allegedly trying to take out President Trump and others at the annual White House Correspondents Dinner in DC last weekend.…