But as long as "everyone does it" remains your attitude towards war, everyone will keep doing it.
That is
not my attitude toward war, as I have just recently stated. War is the worst consequence of the failure of diplomacy, and it is a tragedy whenever it occurs.
Leftist error. You are assuming that diplomacy can prevent all wars. Does it not occur to you that there are those evil enough that they knowingly choose the path of horror?
In children's books, sure. When I was nine or ten, I graduated to reading novels where people had a bit more nuance than simplistic stereotypes of good and evil. More complicated, I found, but more interesting, and certainly more like real life.
I don't know what you mean by "diplomacy can prevent all wars". Obviously, it has failed to do so repeatedly. I am well aware of this. Similarly, I do not believe that medicine can prevent all illness, that environmental regulations can prevent all extinctions, that counseling can fix every marriage, or that loving mommy enough will fix her brain. I
do, however, think that illnesses (of whatever kind) should be ameliorated to whatever extent possible, not intentionally fostered and certainly not celebrated.