Thanks for that. I need to think about it. From that view, "international" anything isn't legitimate. There are always some country(s) where a given act is okay. The USA hasn't signed that treaty against land mines, for example, and isn't onboard with the ICC in the Hague. Malta and Panama do shell corporations that make Wyoming flinch. Banks in Cyprus, Guernsey and Isle of Man are widely considered to exist merely to launder money.
So a country sanctioning or allowing something is a really weak basis, as you point out.
But "countries with X% of the world population" is just as bad. Saudi Arabia is still an absolute monarchy. No telling what North Korea is, but a sanction from there does not represent the will of its people.
Good point! Maybe no "international" anything is legit.