It has been in use for at least a decade, since the Obama administration if not earlier.
We have soldiers, sailors, airman/women, Marines (who really do not like being called soldiers), Coast Guardsman/women, and now the Space Force. Granted, I do not know why "service member" did not catch on. Perhaps because "warfighter" is a bit shorter.
> Granted, I do not know why "service member" did not catch on. Perhaps because "warfighter" is a bit shorter.
Yeah, it's basically this. "service member" is clunky, like saying "person with enlistment".
Warfighter has its own issues as a descriptor but it at least rolls off the tongue better and is easier to read through in policy and regulation to the millions in the DoD.