Possible but not likely.
Is there open aggression directed at the us?
Is this aggression perpetuated by the mexican government?
Is the mexican government unwilling to pursue these lawless elements?
And finally, is there a good reason to think that occupation is the best possible solution?
Yes, fiction -- very well researched fiction.
I mentioned it because it was the first thing that crossed my mind. I'm sure there are better precedents in international jurisprudence for your concern.
I'm not sure. In my country, a foreigner cannot own land. A corporation of at most 40% foreign ownership can own land but no more than that. That is, of course, dependent on the pertinent land laws of a particular country.
The regallian doctrine is based on the principle that the state owns the land within its territory. Private ownership exists at the sufferance of the state. If and when that private ownership conflicts with the very compelling interests of that state, then the state reserves the right of eminent domain. And while eminent domain is subject to compensation, the determination of compensation rests on the state.
Land ownership is, by nature, adversarial. One claims a piece of land for himself 'against the world'. The registration of a positive title is merely a formality to manifest this claim.
So, you can very well imagine how it would be next to impossible for a palestinian arab who does not owe any allegiance to the state of israel, and who cannot demonstrate 'continuous and adverse' claims (since, guess what?, they left the place when the going got tough) could own land against someone who does.
