In the role of both politician and soldier, Bonham was a man of commanding presence, his appearance highlighted by gray-streaked hair, steely eyes, and an immaculately kept beard. His forceful personality was somewhat weakened by a difficult temper and a tendency to mood swings. From his twenties to the end of his public life he struck observers such as James Henry Hammond as "not of an equable temperament, being either full of hope or plunged in despair." High-minded and generous, he could also be condescending, imperious, and abrupt to the point of rudeness; during his Civil War military service, his staff referred to him behind his back as "the Dictator." His frequent squabbling with regular army and West Point-trained superiors such as Beauregard and his acute sensitivity to matters of seniority betrayed the worst traits of the citizen-soldier.
Edward G. Longacre, "Bonham, Milledge Luke," American National Biography Online, February 2000, http://www.anb.org/articles/04/04-00120.html.