I recall meeting a 14 year old American at school who could not believe no one knew who Paul Revere was (albeit now we know a woman rode further and faster than he) I told him that you cannot expect a country to teach its children about its defeats. I didn’t realise at the time that was quite an insight for a 14 year old. As I have read more over my life I realise that the joke we used to have about the Soviets teaching how they invented everything, is less of a joke now we know Persians and Arabs made huge discoveries in the 8th-10th centuries before the Crusades, in science, astronomy, medicine, optics and mathematics.
The western centric discourse in our education leaves out the monstrous warring that gave the western powers their eminence.