Re: I'm confused.
It's not tricky. Veganism is about stopping industrial scale animal cruelty, or at least not contributing to it. It's a very different thing if another nation threatens your homeland. There's no reason why a vegan shouldn't defend themselves, it's not pacifism.
In fact some vegan texts argue that milk production is more cruel than meat production. One involves impregnating an animal and then taking it's child away after a few days, the other just kills the animal. The first results in years of cruelty, the second could represent a year of wandering around a field then a quick visit from a man with a shotgun. Which would you prefer?