State immunity — Jurisdictional immunity — Action for default on government bonds and credit certificates — United States Foreign Sovereign Immunities Act 1976 — Retroactive application — Commercial activity exception — Whether applicable to issue of bonds — Whether applicable to bonds issued in 1916 — Application of doctrine of absolute immunity in 1916 — Settled expectation that State would be entitled to immunity in respect of issue of bonds at that date — Procedure — Service of process — Judgment in default — Grounds for setting aside judgment in default

Governments — Succession — Union of Soviet Socialist Republics — Whether Government of USSR liable in respect of bonds issued by Imperial Government of Russia

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 interests — Relevance — The law of the United States