Vanunu was one of the very few prisoners in Israeli history whose sentence was not reduced for good behavior, nor was he given a single day's furlough. For many years, he was imprisoned in solitary confinement, which nearly drove him insane. Two years ago, he was released and asked to leave Israel.

That's when the vengeful machinery of the defense establishment - Defense Minister Shaul Mofaz, the Shin Bet, and Yehiel Horev, head of security for the defense establishment - went into action. They imposed a series of limitations on Vanunu, restricting his freedom of movement and his right to social contacts. The worst of these restrictions is the ban on him leaving Israel.

The state claims that Vanunu remains a tangible risk to its security. That is a baseless argument, worrisome, immoral and unjust. It is baseless because Vanunu stopped working at the Dimona nuclear reactor more than 20 years ago and it is reasonable to assume that the reactor and Israel's nuclear policies have undergone technological changes that outdate his knowledge; and if not, then the fact that the state of Israel is not working on improving its nuclear capabilities should be a cause for real concern. In any case, Vanunu speaks about what the world already knows and continues to know: Israel is a nuclear power.

Morally and legally, and from a democratic perspective, it is intolerable that someone who has been punished should be punished over and over again for the same sin for which he served such a heavy sentence. It should be remembered that it is precisely through the same argument of knowing state secrets that the Soviet Union prevented Jewish scientists from immigrating to Israel. By the same logic that guides the defense establishment and the judicial system, as long as Vanunu's memory works, he can never leave Israel. Maybe he'll be allowed to leave if he develops signs of senility.

It is easy not to like Vanunu. He has conflicts with many people, including with some of his few supporters. His family has cut off its ties to him. To purposely challenge the restrictions imposed upon him he has violated them a few times, and can expect to be prosecuted for such. He has gone close to border crossings in the territories and granted interviews to foreign journalists. He refuses to speak with Israeli reporters, including this writer. He argues that as long as he is forbidden to speak with foreigners altogether, including foreign journalists in particular, he will continue to boycott the Israeli press.

Vanunu converted to Christianity and is interested in leaving Israel to start a new life and family in a country that will agree to accept him. He should be allowed to do so. True, during the last two years the Supreme Court has accepted the arguments made by the defense establishment during hearings about Vanunu's case. But that should not be surprising. The courts, including the Supreme Court under Aharon Barak, nearly always accepts the defense establishment's requests. They, in effect, are a continuation of Israel's security policy - through other means. It is also true that the former justice minister, Yosef Lapid, approved the package of restrictions that Mofaz and Horev delivered. But what could be expected from the "liberal" leader of Shinui, who on another occasion, when he was a TV personality, proposed using car bombs in densely populated Palestinian areas.

However, his replacement, Justice Minister Tzipi Livni can be expected to behave differently. In a relatively short time she has won a reputation as a judicious leader, who is moderate, reasonable and decent. In an era where responsible and serious leaders are rare, there are many people, inside and outside of Israel, who want to see her as prime minister. But to be such a worthy prime minister, her leadership must be tested. The Vanunu test may not be the most important or popular among those tests. Nonetheless, if the justice minister puts an end to the man's ongoing harassment, which is entirely motivated by the defense establishment's hunger for vengeance over the way he outwitted it, she would be demonstrating that she is made of the stuff from which leaders who are ready to swim against the popular course are made. By doing so, she would demonstrate compassion, healthy logic and a sense of justice toward a man who has suffered enough.