The history of clashes over extraterritorial jurisdiction between the United States of America and other States in the Americas, Europe and elsewhere is a long one. That history is commonly traced back to the antitrust claims arising from the Alcoa case in 1945, in which the “effects” doctrine was advanced in the peculiar and objectionable form in which it is applied, not simply to acts which constitute elements of a single offence but which occur in different jurisdictions but, rather, to the economic repercussions of acts in one State which are felt in another. The conflict persisted into the 1950s, with the clashes over US regulation of the international shipping and paper industries. In the 1960s and 1970s there were further clashes in relation to the extraterritorial application of US competition laws, notably in disputes over shipping regulation and the notorious Uranium Antitrust litigation, in which US laws were applied to penalise the extraterritorial conduct of non-US companies, conducted with the approval of their national governments, at a time when those companies were barred by US law from trading in the United States. It was that litigation which was in large measure responsible for the adoption in the United Kingdom of the Protection of Trading Interests Act 1980, which significantly extended the powers which the British government had asserted in the 1952 Shipping Contracts and Commercial Documents Act to defend British interests against US extraterritorial claims.