A lot of people on HN have either served in the US mil or are sympathetic, and have successfully solved their cognitive dissonance about killing 10k people for 1 soldier.
But you're right, whoever they killed was most often either a civilian, someone defending their country, or someone forced to defend their country from an invader.
While the US soldiers kill either because they believe in the crazy narratives pushed by the US empire or because they want to go to university, and especially because the risk to them is mind-bogglingly low. What I'm saying is: US soldiers are war criminals. Those who find a way to see through their mistakes, whatever pushed them to engage and do what they did, can be redeemed, so I'm not discounting all of them, but so few do.
A thought for Aaron Bushnell.
https://aaronbushnell.org/