Your argument is against the English language rather than HN. "War" has been used to describe things other than "mutual, systematic murder between enemies" as long as the word has existed.
Complaining about using the word "war" when not actually talking about murder is like complaining about using the phrase "I see" to say "I understand."
His argument was that you seem to be under the impression that this dilution has not already happened long ago, which is clearly false. He is not diluting the word war: you are just trying to restrict its usage for some reason.
Complaining about using the word "war" when not actually talking about murder is like complaining about using the phrase "I see" to say "I understand."