State immunity — Jurisdictional immunity — United States Foreign Sovereign Immunities Act 1976 — Commercial activity exception — Distinction between sovereign and commercial acts — Whether entering into a contract a sovereign or commercial act — Distinction turning on main rather than subsidiary terms of the contract — Contract to advise Bolivia on rural development — Provisions for diplomatic, tax and customs privileges — Whether entering into contract constitutes a commercial act — Judgment in default — Grounds for setting aside judgment in default

Relationship of international law and municipal law — Foreign relations interest in litigation before municipal courts — Action against foreign State — Evidence from executive that action affecting foreign relations interest — Relevance — The law of the United States