Well, maybe “proportionate” can still include a multiplier. IOW, maybe the proportionate response to a drone shot down is to destroy 30 of their fighter planes on a runway. But maybe killing 150 people is disproportionate. Of course then the question would be, why not have the generals come up with options for a more proportionate response rather than calling the whole thing off.
Just thinking out loud here...
Yes, I like your thoughts here. To have a list of options, in increasing severity.
Maybe that’s exactly what they are doing.