This is sort of an odd recollection to pop into one’s mind at a time like this, but I remember in some of my readings of soldier accounts from U.S. Civil War that shooting a posted sentry was essentially regarded as murder. This was because the sentry was required to maintain his exposed post on the picket line - essentially a fully upright unmoving target. Shooting a sentry was offensive to sensibilities of the other common soldiers because they, on any another day, might be performing exactly the same duty. Instead, it was common practice to “drive the sentries in” by firing above their heads.
It was an odd, brief humanitarian gesture extended by opposing soldiers to one another in the moments before the deluge of death that was coming.
However, the enemy we now face is so unlike anything resembling a soldier that we must put aside any feelings of common humanity towards them and concerntrate fully on finding and destroying everyone of them along with their enablers.