My Working Theory: In addition to being Sec of Defense, Mattis is also currently an ACTIVE OPERATOR working clandestine missions throughout the globe against Deep State Operatives.
Things got "hot" and in a marvelous and seemingly effortless display of hand-to-hand combat skrills, Mattis KIA'd his target…which were likely several…while taking a light flesh-wound in the process…
Which just proved what I always say…"If you make Mad Dog bleed, you HAVE to die!!!