You've whined about this before, and you remain 100% wrong. You're ignoring both the way the Morality system actually works and the way that combat works.
How many people do you think most soldiers actually kill? Not very many. Moreover, you're being very silly and ignoring the fact that simple murder won't make you unplayable. Even if you treat killing on the battlefield as "planned murder" rather than "manslaughter" (and honestly, barring exceptions like 'snipers' and other people who kill people who aren't actively trying to kill them too, I'd pin it as more psychologically akin to manslaughter as an "impassioned crime"), that'll just reduce you to Morality 2 after multiple such killings, until you reach the point when killing people doesn't mean anything to you.
Not to mention, "I don't kill someone normally, but they were trying to kill me back" is probably worth a dice or two towards the roll, because it's a justification for how killing is not psychologically normal.
And as a genre thing, war in the World of Darkness is something people go off to and come back lessened by. It says that, yes, a soldier who goes out and kills lots of people and becomes acclimatised to it has lost something. It says that psychologically healthy people are not okay with killing other people.