They were also mistaken about his health, personal habits and his involvement in running Iraq.
Mr Nixon also criticised the conduct of George W Bush, under whose leadership America invaded Iraq, saying the former president heard “only what he wanted to hear” on the topic.
During the interrogations, Mr Nixon asked Hussein if he’d ever thought of engaging in a pre-emptive strike with WMDs against US troops based in Saudi Arabia.
According to Mr Nixon, writing in the Mail on Sunday, the former dictator’s reply was: “We never thought about using weapons of mass destruction. It was not discussed. Use chemical weapons against the world? Is there anyone with full faculties who would do this? Who would use these weapons when they had not been used against us?”
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Mr Nixon admitted this was “not what we had expected to hear”.
The main reason the American and British governments used to justify the controversial invasion of Iraq was the supposed risk posed by the WMDs possessed by the country.
When asked why he believed this, Hussein said it was because the Americans didn’t understand the Iraqi people because they didn’t know the language, mind-set of the country, the history and even the weather.
Hussein was executed in 2006, three years after his capture close to his home town of Tikrit at the hands of American Special Forces.
But his predictions were accurate: The country descended into chaos after he was removed from power, and nearly 200,000 people have died in the conflicts that followed.
Iraq is now widely regarded as a failed state, and still suffers from widespread violence, including from Isis, who are currently defending the city of Mosul.