If resources don’t have a legitimate owner, they’re effectively unowned. This is the case of all dictatorships. Any free country can take those resources and integrate them into their system, provided they recognize and enforce property rights. Otherwise it’s anarchism, a dysfunctional hybrid of old dictatorship and American pragmatic profit, not a secure system of property rights.

(Assigning ownership to nation as such wouldn’t fix the problem. A nation without property rights cannot own anything.)