Long before WikiLeaks was divulging US diplomatic cables, the US administration of President Richard Nixon obsessed over government secrecy.

Nixon's presidential library on Thursday released thousands of documents from the early 1970s, including formerly secret national security files on topics ranging from US policy toward Chile under the left-wing Allende government to US dependence on Middle Eastern oil.

A handwritten memo from Nixon's senior aide instructs the National Security Council to exclude Jewish Americans from making US policy toward Israel.

The president's paranoia about supposed enemies conspiring against him eventually led to his downfall.

But as he told Al Jazeera's David Frost in a famous interview three years after his resignation, Nixon felt that he did no wrong.