In fiction Conservationof Ninjutsu
is powerful beyond compare. One ninja, or frankly any humanoid, will have no problem taking out an entire army. Unfortunately for the army's leader, they're not Genre Savvy
. Of course the only thing they can think, and thus shout, when seeing the carnage laid out is, "It's just one man!" or, "What can one man do?"
Applies to any time a character asks what one person can do, whether it be against his own "superior" strength, or an entire country.
Needs More Examples
and a page image if anyone's interested.