Great piece.

Most mass acts of aggression are justified with, "They were OK by the standards of their times." That's true, but not really. Every atrocity that you mention - past and present - has something in common. That something in common is the belief in authority, that some people can do unto others that most cannot.

In Mayan times, under their standards, most Mayans presumably knew that they couldn't just lop off their neighbor's head if their crops were going bad. Yet for some reason the kings or high priests could.

In medieval Europe, under their standards, everyone knew that they couldn't just tie their neighbor to a stick and set them on fire over a disagreement. Yet the church could.

Same goes for slavery, the drug war, and hitting kids. Some people are granted the "authority" to do unto others. Government, incidentally, is only a symptom of authority, and not its source.

In the future, if we want people to look back on our own atrocities with disgust, but not replace them with other atrocities - as is happening today - we will have to work on eliminating that which every atrocity has in common: that belief that some are more equal than others.

The cool thing is, if the belief in authority is eliminated, and something goes wrong in the future (mass-murder, etc.), people in the even-more-distant future won't look back and justify the act as being acceptable under the standards of the times. They will recognize aggression for what it is, and minimize the chances of a repeat.

We'll never have a non-aggression Utopia, but it is a legitimate goal to shoot for.