When asked to stand as rector of Glasgow University, Mordechai Vanunu was flattered but sent his regrets. “Being banned from leaving Israel makes it impossible for me to run your great organisation,” he told his supporters in Scotland. “Even if the ban is lifted, I do not think I have the skills, or the time.”

His attitude changed when told the post was largely symbolic — a quirky feature of four of Scotland’s oldest universities — but an honour nonetheless. Like the motley collection of previous incumbents ranging from Disraeli and Winnie Mandela to Johnny Ball, the children’s entertainer, and the pop singer Pat Kane, Vanunu merely has to chair the court of governors — if he is able.

He was persuaded to put his name forward because it provides a platform for him to propagate his anti-nuclear message. Ten days before Christmas he beat his nearest rival, the former Lions and Scottish international rugby star John Beattie, by 1,033 votes to 793.

As Vanunu told me when we chatted on the phone on Christmas Day, he was surprised how many students had voted for him. They were only infants in 1986 when he paid a terrible price for exposing his country’s nuclear secrets.

In August that year Vanunu was in Australia on a global tour when he decided to reveal to The Sunday Times details of Dimona, the underground plutonium plant where he had worked as a technician. He handed over to me more than 50 photographs of the equipment he had operated and of a network of underground laboratories making components for a range of thermonuclear weapons.

Within a few weeks, we had flown to London for further debriefing by weapons experts. While strolling in Regent Street, he had met a woman and begun dating her. And without telling anybody, he had accepted her invitation to fly to an apartment in Rome for an amorous interlude. Then disaster struck.

The woman, Cindy, was an agent of Mossad, the Israeli secret service, and her back-up team were lying in wait. His kidnapping and subsequent treason trial in Israel was like a Hollywood horror story except it was the real thing.

Fast-forward to April last year when the world’s press and television arrived en masse to record his first moments of freedom since the kidnap. They gathered at the grim jail south of Tel Aviv where Vanunu had been forced to spend 18 years, more than 11 of them in mind-numbing solitary confinement.

Calm and dignified as he approached the throng of journalists, he managed to control his anger but not his contempt for the Israeli authorities. He accused them of maltreating him because he had converted to Christianity. He proclaimed he would continue to campaign against nuclear weapons in the Middle East and not for a moment regretted his decision to become a whistleblower.

He went on: “I am proud and happy . . . I succeeded to do what I did . . . (It is) a symbol that a free man can survive, a free spirit can exist. There is no human being that can destroy the freedom of speech, the will of freedom, the man who wants to be free.”

This defiance is surely what appealed to the Glasgow students who voted him rector. In a world where the threat of illicit WMDs is ever present, he has become a unique figure — a humble technician whose courage and endurance have made him a figurehead of the anti-nuclear movement.

The question of who was really behind the kidnapping still needles him, and he promises to air that issue more publicly when he is able to take up the Glasgow post. The assumption has always been that his capture was entirely a Mossad operation. But when he left jail, he said something that the press overlooked.

Speaking about his trip to Rome, Vanunu said: “As soon as I went into the apartment they attacked me, one Israeli and one Frenchman. They drugged me. They took me in a car to . . . an isolated beach, [to] a commando boat, and from the commando boat to a small yacht. There I was chained for seven days.”

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