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There is more to military units than hardware. There is the character of the unit's personnel: their strengths, experience, and knowledge, their ability to get along and work together amid the horrors of the battlefield. There is an almost undefinable quality. That quality is the Marine Corps' secret weapon. Their edge. That quality is their ethos.

Tom Clancy (1996). “Marine: A Guided Tour of a Marine Expeditionary Unit”, p.2, Penguin
There is more to military units than hardware. There is the character of the unit's personnel: their strengths, experience, and knowledge, their ability to get along and work together amid the horrors of the