State immunity — Jurisdictional immunity — State corporation — Whether to be treated as alter ego of the State — Whether entitled to immunity from suit — Nature of separate legal personality — Whether corporation liable in respect of acts performed by the State — Whether debtor of corporation may assert counterclaim in respect of expropriation by State — Law determining effects of corporation’s personality — Whether matter of international law — Whether equitable principles require Court to ignore corporation’s separate personality

Relationship of international law and municipal law — Customary international law — Application as part of United States law — Principles common to United States federal common law and international law — The law of the United States