Omaha Beach Scene from Saving Private Ryan.

Many historians agree that the opening scene of opening scene of Saving Private Ryan is one of the most authentic depictions of battle ever rendered cinematically. Click the link directly above to remind yourself of what happened at Omaha Beach.

Based on thirty-five years of research on warfare, I would say that this scene is not anomalous. In fact, it captures the essence of warfare and battle: young men being slaughtered.

If one approaches warfare and battle from an empirical perspective, this would be as good a hypothesis or description of warfare as one might put forth, encompassing many wars (in many different cultures) and many different battles: Warfare as the occasion when young men are slaughtered.

On the other hand, some people--not actually familiar with the reality of battle--put forth a theory of "male aggression" as the cause of war. No military person I've known--or serious historian--entertains this hypothesis to account for the battles with which they are familiar. 

Please watch the scene from Saving Private Ryan carefully: the sadness, the pathos of young men--many barely out of their teens--being slaughtered.

Then reconsider the hypothesis of "male aggression" or the strange theory that these young men are engaging in battle (at the behest of General Eisenhower) because they have inherited a gene that makes them "killer apes."