Fine, so apply my response to your earlier sentence, A mi sheberach exists for soldiers and not for firefighters. Why? I don’t think it matters.
It’s existence is not for the welfare of the soldiers; it exists as a political statement. Haga atzm’cha; if there were as many firefighters in danger as soldiers (your distinction regarding the source of danger is incomprehensible to me), would the tefillah l’firefighters be instituted? Of course not. They we would be (as they and the soldiers are) included in existing tefillos.
As far as I’m concerned, it doesn’t exist; we don’t say it in my shul. So, let’s start from square one. Should we compose and say every Shabbos a tefillah for soldiers for no political reason? The clear answer is no, but the OP says that our not saying it shows poor middos.