I think this is a very good question, which actually can be taken much further, perhaps much more of our behavior leading to war is also learned. I mean the business of profit, and actually energy slavery.
We still do it, actually all of us, we just bury it so deep in our psyche now we barely ever think about it, but this is how all hierarchical society and business works, and we none of us have a choice but keep practicing it to live at all. "The system" removes any and all options of dropping out of it, by removing even the means to keep obtaining the energy we need to metabolise every day, without in the end, begging in the street for food.
Right at the front end of it, the proposition is this: our mission is to con more energy out of our fellow humans by making them feel obliged to give it to us, we have to continuously, successfully persuade the majority of people around us, to provide us with more energy in than out, and this has to propagate through all the supply chains we personally depend on, until eventually it gets to the planet, which is the only thing that can provide more energy out than in, for any length of time. The planet is in this way continuously robbed of energy, and the temperature keeps going up, because the net effect of taking things from the planet which were not heat, and converting at least part of these to heat, is to push up the planetary temperature, and we disguise the temperature rise by claiming it is due to greenhouse gases, which is a lie because the atmosphere is adiabatic, so more profit can be made in the lie, by green business for yet more profit.
I point all this out, having studied and traced it now for seven years, after a long career as a Systems Engineer, even at PhD / Chartered level, and everyone ignores, preferring to carry on, rarely if ever acknowledging it, isn't that weird?
To me it has to be learned behaviour that we can ignore such damning evidence of our own harmful, actually existentially damaging behaviour.
This has got to be learned, there is no way we evolved to become like this to be become ultimately hostile and threatening to all life, especially even after I also show there is a perfectly fine technical way out of it all, and folk dismiss it as Utopia.
Yet not taking the solution leads to genocide and a burning planet, the genocide not even fixing anything, it's just our final gesture of "honor" that we will end ourself after all the damage is done, like a parent committing suicide as well as the murder of their kids.
Is any of this common sense?
It has to be all learned behaviour.
Somebody else asked the fifty billion dollar question already, who, or what trained us to do this? How was the training done? I think knowing the answer to that would help a lot.
BTW, I collected my first ration of food from the local food bank yesterday, after sinking about 100K of my own funds and abut 500K of my own professional time in this effort until now, and still I can't raise a cent of funds from crowd funders or book sales, to continue the effort, on behalf of all people.
This is surely something weird, that not a soul seems interested to help me carry on trying to help all of us, it's very very weird I find myself in this position I think.
https://www.amazon.com/Interview-Ai-Part-Multiplier-Framework-ebook/dp/B0CHGFKQVB