the soldier's "cause"... it could be many things.
from saving a small farming community from natural disaster, to seeing through the conclusion of the second world war and the liberation of Eurpope, it could be defending the home shores from foriegn invasion, or entering a dangerous area to evacuate the stranded, sick, or wounded in need of help who cannot help themselves (picture elderly or sick stranded on a volcanic island, or those who are displaced after a hurricaine or tsunami).
point being... the mission scope of a soldier is multifaceted... soldiers do not always carry rifles, and their mission is not always to kill, it is often to serve, protect and rescue etc.
the Merc and the Assassin are not paid to perform these services, only to kill.
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