SS-18 ICBM
Oscillator

Spoiler :

I'm leaning with headshot dude. They were just trying to defend their own sphere of influence.
A determination of justification cannot be established based upon the limited facts we are given. Justification of a combatant's activities can only come based on the circumstances of a particular battle. To the individual combatant, it doesn't matter whether the greater conflict is just or not; unless these chumps are heads of states or generals then they have no reason to justify the greater war they are involved in. Enlisted men are only responsible for their own actions. Unless there was some egregious violation of conduct, such as if one of the men was clearly a medic, then no justification is required from the combatant.
The unjustified action from this comic comes not from the principles involved but from the cartoonist himself. Presuming that an individual solider should answer for the greater policies of his nation is simply absurd and only serves to dumb down the question for the sake of a cheap laugh.
I'll be on your side if you'll be on mine. Provided I can bring my friends.Who's on my side?
Needs more context.