Land and Ownership

In this weeks Parshah (Massei) it is written:

And you shall dispossess the inhabitants of the land, and dwell in it; for I have given you the land to possess it (Numbers 33:53)

This reminded me about something I was thinking about a short while back, land ownership. Now it makes sense to say that since Hashem created the land He has the right to give it to whomever he wants. You make it, you own it. However when looking at other situations of land ownership it becomes more complicated.

For instance in the United States people own land. Some people not only own land but the also own the resources that the land has, oil for example. If someone created these lands or these resources themselves it makes sense that they should own it. However, no one in the United States created the land or its resources which they now claim ownership of. They may cultivate the land for its natural resources, but they haven't really created the resources themselves.

So why do they own it, well either they inherited it, it was given to them, or they bought it. Now that all seems perfectly reasonable, but looking back far enough that is not how the land was originally owned. What essentially happened is that Europeans came to the land and by virtue of getting there "first" or conquering it from someone else (in essence stealing it from someone else) they then claimed ownership of the land.

Is that legitimate ownership? Do the foundations of our claim to owning any land or resources in America have any grounds (puns intended)?

Going a bit further if Hashem gave the land to someone do they really own the land? If so, it does not seem like Hashem has the moral right to take it away and give it to someone else. If I gave someone something, it wouldn't be right for me to take it away from them against their will later on, when I feel like it. If not, then in what sense is it given?

Comments welcome.