It seems to me that cruelty, aggression and the need to destroy is as big a part of the human psyche as love compassion and any other "self" related thought process that separates man from the rest of nature.
It's a trait of intelligence becuse you have to be self aware in order to be cruel.
We all learn from an early age that these feelings must be contained and subdued at all costs.
Six of the ten commandments deal with control over aggressive and cruel behavior.
Why? Because it's as strong and natural to all of us as love and compassion.
People hurt and get hurt all the time because of cruel and agressive behavior.
Why are we built like this?
Almost all life feeds on other life in order to survive. The only ecxeption I think ,is plants. Everything else has to kill in order to survive. Maybe aggression and cruelty stems from this fact? Maybe there is a correlation between the urge to survive and the need to be capable of killing in order to do it?
If so, then maybe cruelty and aggression are intelligently refined versions of a primeval survival trait?

And where does it start and ultimately end?
Rapists, murderers, domestic abusers and bullies are cruel and aggressive.
Columbian drug lords are cruel, they make money by preying on people's need to escape everyday life through narcotics.
What about Philip Morris International? They do exactly the same, only it's tobacco and not considered anyway near heroin. Still they know perfectly well what it does to people's heart and lungs in the long run.
What about General Dynamics? Can they be considered cruel? They make the Abrams main battle tank knowing perfectly well that it's intended to feed government sanctioned cruelty and aggression.
What about Albert Einstein? His involvement in getting the US started on the Manhattan project ultimately ended in over 200000 dead japanese with two bombs.
Was it cruel, to use his prestige in order to get Roosevelt into the atomic race, knowing probably better than most what effect this weapon was capable of producing?

What about the entertainment industry? all the inhuman violence in films and games? I very much doubt that you can call most people in these businesses cruel, and yet they gladly portray anything from shooting, raping, stabbing, torture to people eating eachother, armageddon and anything inbetween. Are they projecting a form of cruelty, destruction and aggression?
All of this sells like hotcakes as well, which brings me back to all of us who are entertained by this stuff, the worse the better.
Why? Why do I enjoy Batman much more than some sticky Hugh Grant romantic comedy?
I mean these feelings are the ones that start wars, it's potent stuff. Aggression and cruelty are extremely powerful tools. Adolf Hitler was an angry man and he set the whole world on fire.

What about all of us here on DA that design and glorify weapons as an artform? Is that also a watered out form of cruelty and subdued aggression?

I am wondering,since these feelings  and urges most likely  cannot be rooted out without also removing a big part of what it means to be human and self aware,
can they instead be harnessed, and directed towards other uses that are not destructive?
In a sense that is what the entertainment industry does, isn't it? An enormous branch of society focused on portraying violence so that we can feed the urge without having  to act it out irl.
I sometimes wonder if this is planned out to a tee by the governments at large, or if it has come as a result of popular demand.
The Colosseum in ancient Rome was built to feed the public's blood lust and thirst for excitement in order to avoid riots. It was one of the very first major crowd control devices.

We all love violence, destruction, aggression and cruelty in one form or another. It's there and we cannot get rid of it. It's an enormous and in peace time, mostly untapped resource.
What if it was possible to use the force behind these behavioral traits to build society istead of trying to tear it down all the time. Not as crowd control, but as tools for the benefit of all.
I am talking about a systematical mapping of the feelings that manifest themselves in cruel , destructive and aggressive behavior and then cannelling it as incentives for positive
behavior, production.
Could it be done? Imagine a world where there was no aggression or cruelty left. All the energy they produce is instead channelled towards production and creation.

Would you want to live in a world like that?