So what did the soldiers do who didn't fight?

At the beginning of 21 Bridges Det. Andre Davis has to attend a hearing, presumably for killing on duty. He is called out for supposedly using his gun too often but he stands to it and believes he was right in every case and then says:

During the Civil War, some soldiers just kept loading their muskets without ever firing. Five or six balls loaded on top of each other. In Vietnam, only 30% of frontline infantry soldiers ever fired a shot. So, ten soldiers in battle, only three truly fighting...What do you imagine the other seven were doing?

But it is not clear to me what the answer to this rhetorical question is supposed to be. What is he trying to say with this analogy? Presumably he is one of the 30% who "truly fight", but I can't imagine that he's implying that the soldiers who didn't fight didn't do anything, rather on the contrary. But if he's trying to say they prepared for war or did their part in it, it's not clear to me how that is supporting his case or what point about his behaviour that is supposed to make.

While the funeral at the start as well as Andre's talk of justice transports a very old-testamentarian vibe and he certainly is intoduced as a man who means serious business, it is also made clear throughout the movie that contrary what everyone thinks of him he's not a hot-head driven by revenge for his father and doesn't actually kill if it isn't necessary. But I'm also unsure if that first hearing scene is supposed to guide us on the wrong track that everyone else is on about him being a "trigger" or "out for justice" or if that dialogue is already trying to fight that prejudice and show that he's a "good guy".

So what answer does he expect on that question about the soldiers who didn't fight and what point about his character and his actions is he (and ultimately the film) trying to make there?