"He confessed that Carly Simon's 1972 hit song "You're So Vain" was, in fact, written by him.In the years after working for Kennedy, Jack "thrived" on fear, bow hunting polar bears, climbing Mount Kilimanjaro, once driving a rental car into the Hudson River to practice escaping, showering with Greta Van Susteren and overcoming a peanut allergy through sheer willpower.