Yes.
Yes. A person does not have to provide proof of citizenship to purchase real property in the US.
france
Yes, if the property was acquired legally, meaning any income used to purchase the property was properly claimed and taxed, valid identity documents were used such as SS# and so forth.
japan
Minister of Foreign Affairs or as used in the US, the Secretary of State.
The US did not purchase any foreign lands in 1877. In 1819, the US purchased Florida from Spain for $5 million.
for the us is migrating
No. But only if the person already has US permanent residency.
Yes, you can either sue them in the US, if the court has jurisdiction over the matter and some property or person in the US, or go sue them in the country where they are found or reside.
No. The person will need a pardon. (Or a GOOD Lawyer)
NO
No, because the property was supposed to be sold for 15 million. It was sold for a cheaper price.