Of course they are irrational. But manhood is not rational. It is not rational to die to protect others. But it is not built on individual reason. Without the guidance of men and the traditions of manhood, boys pick up what clues they can from the media, or gangs of one type or another, and they often make a botch of their growing up.
Violence is the only consistent message they see.
But while willingness to risk violence against evil is part of manhood, without the full tradition of manhood and the moral guidance it contains, male aggression can convert boys into monsters that prey on society, the Grendels lurking in the dark, the predators who shoot women and children. It is very, very easy for a boy unguided by the inheritance of the traditional male script to go wrong. The chances are that, because this is a men's issues newsletter, it's been quite a while, if at all. If you did go, the chances also are that you and the other men were in the minority. It's been that way for a long time.