Yes, illustrating possession is/was not ownership, as I've said.
Actually the law would say the opposite. That is the point.
There is very obviously a large difference. As you might find were you to wander up to the gates of Graceland, Fort Knox or 1600 Pennsylvania Avenue and make your claim to own them.
Why exactly is there so much gold in Fort Knox? Because the government decided it had a claim on it by virtue of the fact that FDR wanted it and the government had an army and police force to ensure his will was done.
Here is an experiment for you to try out. Try defrauding the government. On one side the government may say that stealing is wrong, yet at the same time the government acts as an enabler of theft. So the government, at the same time, can say that a person owns (because it was given to you) and does not own something (because you effectively stole it). Seems a bit contradictory.
The fact is that, even in our greater society, the society's decision about whether something is owned or not really comes down to whom best can game the system. That is not actual ownership.
A society can decide whatever the hell it wants but it does not change ownership. You keep mistaking LEGAL ownership of ACTUAL ownership.
Also, what about conflicting claims between societies? A town in New Mexico was told that they were not allowed to cut a fire break. The town said we need to cut those trees down to help control wildfires. The standoff that occurred ended after the Forestry Service threatened to arrest anyone who was cutting the fire break and the local sheriff threatened to arrest the arrestors for false arrest. Then the Feds backed off. What happened there? Two societies had a conflicting claim. If society decides ownership then shouldn't the feds have stopped the citizens? They are the overriding authority within our system and they have to maintain order right? Apparently one society won the claim despite the fact that the other society said that they didn't. So both the feds and the town's people own the land but no one is admitting the other (although the first tree cut down was apparently done by their congressman). In fact one of the societies that claimed the trees is actually not enforcing its claim at all. If it does not have the ability to enforce its claim then its claim is effectively worthless (as your White House example illustrates).
This brings up another problem, if society decides ownership then which society. Depending on how you look at it I could be considered a part of a few dozen societies. Does my familial unit override my federal society? In some cases it apparently does since the feds back down. But if the societies claims can be so easily altered by another society (or even an individual) how can you say they decide ownership? At best you can say that ownership is a perpetual fight amongst different societies and individuals. That I can get behind but the idea that society decides ownership is fundamentally flawed.
Chimpanzees have society too, you know. So do dogs, rabbits, whippoorwills and ants. Unless you are a creationist (and I suspect you are not), the first humans were born and brought up by prehumans who bequeathed their prehuman society on as well as their prehuman genes.
And none of those are human societies. Society did not simply come into being it had to be formed and since groups cannot be formed without the included parties it means that humans predate society.
Humans intrinsically have society; individuals sum together to make society and are also shaped by it return.
Then why are there humans who live without society? If humans intrinsically have society then what happens when a society implodes on itself? People leave and form a different society. The death of a society does not mean the death of its people. That shows that society, in and of itself, is not necessary but the fact that societies are typically reformed means that humans prefer it. Preference does not mean that something is intrinsic.
Now, we could carry out a thought experiment where we put ten previously unrelated individuals on a desert island and they would (presumably) form a new society; but even then, they would carrying forward ideas of how to relate to each other from their previous societal experiences.
So you are saying that the society would have to be formed and that it would not simply come into being by virtue of their existence.
Humans almost certainly instinctively understand one concept relating to ownership: that things can (and should?) be owned. However, that in and of itself means very little, as it does not resolve ownership.
When we talk about ownership rights, we are thinking about 1) what is property that can be owned and 2) who/what owns what property. And here, the differences are vast. Some societies had large scale communal ownership and others not, with all the spectrum in between; did not understand ownership of land; practiced slavery; and so on ad infinitum.
Actually those differences are minor to the overall. The fact that people who make things are the owner of that thing (assuming it was not made in someone else's name) and other similar principles is more important. The fact that some societies have communal hunting parties and some were more individualized (usually do to the game and technology in question) does not change the base idea of ownership. It is only a change in the method of gathering/making/etc.
Societies do evolve, but so what? We might ask that if we have an instinctive concept of ownership, why don't we already practice it instead of having to evolve to it? How come so many different attitudes to ownership exist and have existed if it's instinctive?
It exists that way because we still have free will. And with that free will we change our societies and teach our children new methods. However that does not change the fact that there is little variation in the BASE idea of ownership.