According to Tom Gjelten here's what happened in Chile in the early 1970s: "[Pres.] Allende was implementing socialist economic policies in Chile, with disastrous results." And because of these disastrous results, "Gen. Pinochet finally agreed with other military officers that they had to stop Allende."
Later in the piece Gjelten does mention that the US supported the coup, and tells us that "having secretly undermined the Allende government, U.S. officials were quick to praise Pinochet when he brought in American economic advisers and instituted radical free-market reforms in Chile." So which was it--the disastrous socialism or the secret undermining of the US? The paper trail clearly shows that the coup was made in the US and supported for years of brutal repression.
Finally, in the mixed-up history of Gjelten-world the Chilean dictatorship ends - not because of the bravery of opponents of Pinochet and human rights activists- but due to efforts of the United States and Elliot Abrams! Yes, Abrams, the pardoned convict of Iran Contra and point man for torture and dictatorships throughout Latin America in the 1980s.
If you get your history of Latin America from NPR, you will have a very strange understanding of events there - one that would, however, square well with the human rights thugs who have found a comfortable home in the current Bush administration.