You're missing the point - not everyone has the privilege to consider the cause.

Even now as a civilian in healthcare, which sounds infinitely more benign, I'm stuck working for a different flavor of orphan grinding machine in exchange for a paycheck. ...but does that mean I should personalize the evil shit this industry does, like refuse care if someone's too poor, or do provide care but financially ruin them in the process? I'm a surgical tech, soon-to-be nurse: I can't control any of that shit. Should I quit in protest? Cuz that won't change anything outside of severely reducing the quality of my own life.

Same is true of the military: you milk a living out of a shitty system. Are there other options? Sure, but the vast majority of those are shitty too.