Technically they own the building, we gave it to them. We however own the airspace around it...be fun to watch them try to get to their little building with the military chasing after their coattails.
Since the UN whines about "aboriginal rights", lets get some representatives of the tribe to which Manhattan Island originally belonged. The Indians could protest for the return of that particular piece of land. Heck, it would make a spiffing casino and hotel.