We have a huge problem with foreign countries buying up our land and stripping it of resources or using it for nefarious purposes. There have been reports of china buying land here and stripping it of all of its top soil and shipping it back to their country.
If you are a sovereign nation or work for a sovereign nation you should not be allowed to purchase american land. Infact i would say that it should be considered that only American citizens are allowed to purchase land. This would also prevent foreign companies from profitting off our resources as well which would benefit our citizens in the long run, giving them the ability to use those resources.
I could see this potentially hurting the economy in the offset but helping it greatly in the long run.