According to an army grunt friend of mine, there's a truism in his profession which goes "Friendly fire... ISN'T!"
Joking aside, I would assume current IFF systems let you define anything not explicitly friendly as hostile - what with shifting alliances, armament development consolidation &c - the issue being how many backdoors there are. I take it as a given no US-made missile can kill a US-operated aircraft, regardless of what the operator of the missile desires. (Same goes for French, British, Russian &c)
> I take it as a given no US-made missile can kill a US-operated aircraft,
I'm not so sure about that. That would require that all US made missiles have a "disarm" signal that the operators cannot override. Maybe for weapons we sell that is okay, but for our own use, that strikes me as too much of a liability if that signal ever gets compromised and spoofed.
Joking aside, I would assume current IFF systems let you define anything not explicitly friendly as hostile - what with shifting alliances, armament development consolidation &c - the issue being how many backdoors there are. I take it as a given no US-made missile can kill a US-operated aircraft, regardless of what the operator of the missile desires. (Same goes for French, British, Russian &c)