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

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 he did no wrong.

Nixon's presidential library released thousands of documents from the early 1970s on Thursday, 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 East oil.