I can tell you the difference...first, the killing of enemy who surrendered was done in the heat of the moment, kind of like the justification you noted for killing a rapist, and second, the process of accepting a surrender endangered American lives, as a lot of them shammed surrender in order to kill Americans and themselves in suicides. And third, the act of taking prisoners back to a POW holding area over dangerous ground was perilous to guards assigned to these tasks.

There simply is no parallel to war and other circumstances (as Askins was in). A WHOLE different set of rules applies.

Not many problems you can't fix
With a 1911 and a 30-06