In 2016 she ran for the top job, Secretary-General, and her tilt is documented in a new film called My Year with Helen.

The film exposes the institutional sexism of the UN, which has never had a female head, as well as the organisation’s Byzantine processes, and the overweening power of the five states who are permanent members of the Security Council.

These states can veto candidates for Secretary General, and three of them vetoed Clark: China, the United States and France.

Clark notes that she comes from “a small independent-minded nation which has been known to speak truth to power”, and believes her country’s position of nuclear disarmament, the Iraq invasion and human rights in China would have irritated those states.

But, she says, “one would have to be blind to reality to say that gender wasn’t a factor”.

“I never had a glass ceiling I couldn’t eventually smash my way through, until I went to the UN,” she told the lunch.

The first many Australians knew of Clark’s candidacy was when our own former Prime Minister, Kevin Rudd, ran against her as regional candidate, only to have another former Prime Minister, Tony Abbott, back Clark for the job over him.

On gaining power, Malcolm Turnbull told Rudd that Australia would support his candidacy, but changed his mind to support Clark instead, much to Rudd’s disgruntlement.

Turnbull reportedly told Rudd he was temperamentally unsuited to the role of Secretary-General, and lacked interpersonal skills. Would Clark agree?

“I think I’ll stay out of that one,” she says with a grim laugh.

“If [Rudd] hadn’t been a candidate, Australia could have been more supportive of me, but I think the whole nature of the incident as it blew up made that impossible.”

Clark is in regular touch with Julia Gillard - “I had an email from her today” - and says she was similarly characterised as a “Lady Macbeth” because she was a woman who took power from a man.

“That brands you as a tough woman … it takes a while to get that stuff out of the main narrative. I mean if men do it are they ever called, you know, Richard the Third?”

She has no advice for New Zealand Prime Minister Jacinda Ardern (who worked for her briefly as a university graduate), because, she says, Ardern is her own person.

But, she says, “I will go to her defence on anything”.

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