I never really had this interpretation of Shin and co. but it's an interesting take. But the reluctance of war is why they keep fighting to fullfil the dream of unification, which will end all war for good.
Like I said, read 798 and 799. Riboku offers a perspective that kinda touches upon his...
The ranks ultimately don’t matter, it’s the feats that should be accounted.
And he has killed enemies that are not only stronger than Bihei, but also higher rank.
For example, this which happened before the assassin arc
He is a general^