The modern concept of a combat leader usually envisions a hardened veteran
moving behind a battle line of his men, exhorting, encouraging, punishing,
rebuking, correcting, and rewarding them. But combat leadership has not
always been like this. Armies have always had leaders, but the Romans were
the first to take proven warriors and systematically develop them into
professional leaders starting at the lowest levels. Prior to this time,
leaders were usually expected to get into the battle and lead from the
front, but the Romans were one of the first to also place leaders behind
their men in an open order of battle. The influence of this kind of
leadership was one of the key factors in the success of the Roman way of
war. The process of having a respected, proven, small unit leader moving
behind his men and demanding effective killing activity from them has
continued to be a key factor in effective combat in the centuries to
follow. (The fact that he does not necessarily have to personally kill the
enemy provides a diffusion of responsibility, which also enables the
killing.) This kind of leadership largely disappeared along with the Roman
Empire, but it appeared again in the firing lines of English long bowmen,
and then it appeared as a systematically applied factor in the firing lines
of the successful armies of the gunpowder era, and it continues up to
today. Lt. Col. Dave Grossman, On Combat
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