The primary reason Donald J. Trump fired F.B.I. Director James Comey was, simply, because he could. It is his firing of people that somehow satisfies his rather insatiable thirst for power. It was, as you will remember, the key component of his television show, the Apprentice. “You're fired!” was the signature line of that show and it served to demonstrate for all to see who, exactly, held the power. Donald J. Trump.