Three decades before the 2001 al-Qaida terror attacks on the US, September 11 was infamous for another bloody event which ended one era of history and brought forth another. The 1973 military coup in Chile installed General Augusto Pinochet as the dictator of a regime that tortured, killed and disappeared thousands in the name of fighting communism. Salvador Allende, the first socialist in the Americas to take office via the ballot box, killed himself as troops stormed the presidential palace. Under Pinochet, parliament was closed, political parties outlawed, and media outlets shut down. Chile became a test-bed for the “shock therapy” policies of the University of Chicago economist Milton Friedman. The death of democracy was undoubtedly hastened by the actions of leading powers, including the UK and Australia, but most notably the US. Shamefully, Conservative governments led by Edward Heath and Margaret Thatcher resisted helping Pinochet’s victims because of sympathetic attitudes towards the coup. The Labour governments of 1974-79 ran a more ethical foreign policy, accepting Chilean refugees and imposing sanctions on the junta. Pinochet cheated justice through death in 2006, though he died in disgrace in Chile after judges charged him with human rights abuses. He spent 16 months of ignominious house arrest in London. But his ghost still hovers over his country. Last month, Chile’s president, Gabriel Boric, formally launched the nation’s first plan to search for the victims of forced disappearance and political execution under the dictatorship. Mr Boric, who invoked Allende in his inauguration speech, is Chile’s most leftwing president since 1973 and rose to power after a “social explosion” against inequality. An unequal nation has produced polarised politics: Mr Boric’s main opponent is a far-right Pinochet apologist whose party controls a decisive bloc on the committee the president set up to rewrite Chile’s dictatorship-era constitution. A decade ago, polls suggested that one in eight people in Chile did not see the ousting of a democratically elected leader as wrong. That’s now more than one in three. Some accept human rights abuses happened under Pinochet but believe these were excused by superior economic performance. This is false. Chile’s free-market transformation should not be considered a success. In September 1973 this column saw Allende as a “well-meaning man” who failed because he made powerful political enemies, mismanaged the economy and fatally put “ideas into the heads” of generals by appointing them to his cabinet. What was not known then was the extent of a covert US intervention. That only emerged a year later when the head of the CIA admitted spending $8m (about $45m in today’s money) between 1970 and 1973 to make it impossible for Allende to govern. Self‑determination was for like-minded friends. The US government continues to keep secret records about its role. Washington should come clean, as the Chilean coup is seen as part of a decades-long attempt to destabilise leftwing governments in the region. Clearly US national security doctrine was indifferent to dictatorship and legitimated dirty wars. This was wrong. Washington should say so. The US remains self-interested, inspiring fear in the continent. Whether it is sanctions on Cuba, claims that aid is being used against the Mexican government or an IMF-forced depreciation in Argentina, the shadows cast by September 11 1973 are lengthening.