State immunity — Jurisdictional immunity — Commercial activity exception — Requirement of substantial contact with the United States — Recruitment in the United States to work in Saudi Arabia for non-sovereign entity — Whether eventual employment in Saudi Arabia by State corporation constituting substantial contact — Requirement of direct effect in the United States — Whether financial hardship suffered on return to United States following breach of contract abroad constituting direct effect — United States Foreign Sovereign Immunities Act 1976 — The law of the United States