"None of our special forces knife tactics, 1. sneak up 2. grab sentry from behind, hand going over sentry's mouth 3. plunge knife into sentry's carotid or kidney 4. try to hold sentry's arms down until he loses consciousness due to hypovolemia to keep him from giving a warning, firing off a round, etc., come close the simplicity and sureness of 1. whack sentry in skull or neck with a tomahawk 2."