I don't believe I have confused anything at all.
You are claiming that oil, underneath land which is claimed by a sovereign nation or state, can be claimed irrespective of the land which covers it where nobody has stepped forward to challenge the claim.
I disagree. I believe that it is necessary to first secure the rights to the oil before drilling. Only if there is no controlling authority of that land (ie; it is part of no sovereign nation or state territory) may you make a claim to it. (unless the nation or state has provided specific procedures for taking posession of unclaimed land) And if you are going to make a claim to the oil, I also think you must claim the terriritory as well.