Anthropic is far from the first first Silicon Valley giant to trigger US government export controls. Apple turned the prospect of a 1999 export limit on the Power Mac G4 into an ad campaign.JOHN G. MABANGLO / AFP via Getty ImagesSteve Jobs once turned the prospect of a US export restriction into a marketing moment.In 1999, Apple's Power Mac G4 "supercomputer" exceeded the allowed computing threshold for US exports to some countries.Apple release…