By the same token that the proof of the pudding is in the eating, the proof of the leader is in the leading. After two stunning victories at the polls, Sharon has begun to nosedive.

Paradoxically, this is happening just as he has reached the stage of leadership where he is ready to launch a historic move involving withdrawal from Gaza and evacuation of 21 settlements. It is happening just as he has emerged as the first Likud leader since 1967 to recognize that the world has changed and there are limits to what military might can do in the war on Palestinian terror. The fact that Sharon fathered the settlements and told anyone who would listen how important they were for Israel's defense, along with the fact that he is the man who founded the Likud, have imbued his initiative with moral force and credibility, in Israel and abroad.

There are people, particularly on the left, who say Sharon has been bluffing all along. They claim he never meant what he said and would never do it. His own camp, on the other, has been much more believing - especially the right-wing extremists and settlers. They have made up their minds to shoot him down politically (and from what the Shin Bet says, also physically) lest any precedent be set on giving up parts of the "Land of Israel." Although most of the public supported his plan in the surveys, Sharon has found himself hobbled and booby-trapped by his own buddies.

True, he has suffered a series of upsets: the party referendum, the Likud ban on bringing Labor into the government (although this is none of its business), the poor show of hands for his speech at the opening session of the Knesset. All of this has created the impression that Sharon has lost his magic touch in politics and his feel for reading the political map. A major league player in the political game, he has clearly underestimated the strength of his own teammates' opposition.

"Show me a lucky general," Napoleon used to say. Sharon the politician has a lot in common with unlucky generals. The continuation of his career and his Gaza evacuation plan have been commandeered by the caprices of political parties - first and foremost his own. Shamed and humiliated, the question is whether he still has the strength to carry out the disengagement.

Right now, the plan seems stuck. Sharon is at total odds with his camp, bringing to mind the standoff between Mapai and Ben-Gurion in the days of Rafi, which ended with the founding father being banished from the party. The difference is that B-G was at the end of his road, while Sharon is a Likud asset. He brought his party two landslide victories and doubled its strength in the Knesset. Without him, the Likud will probably revert to its natural size. But in politics there is no such thing as gratitude. Everything is calculated.

Sharon erred in not making sure he had a core of support before he began, and in not moving quickly enough to implement the pullout. He made a pile of mistakes that he would never get away with in another country. But this is not another country. Around here, we don't work by the textbook.

"Cats calculate their end backwards," sings Shlomo Artzi. What the songwriter meant, no one really knows. But in our politics, everyone is busy calculating the leader's end. Apart from Yitzhak Shamir, no prime minister in the last 20 years has completed a full term.

Evacuation can't be taken for granted anymore, say Israel's political pundits - and that makes the question of who is in the driver's seat all the more critical. Exactly one week before the U.S. elections, the Knesset will be asked to approve the government decision on evacuation. We don't even have to imagine what the president-elect will think of us if the bill is struck down - especially if it's Bush.

But according to a Sharon insider, this "poor Samson" image is misleading. Sharon, he says, has not lost his vision. He is more determined to disengage than ever - and he has a whole range of options in his basket. To carry out the plan, a broad coalition isn't necessary. As long as most Israelis support it, the resolution can be passed and implemented on the strength of a one-vote majority.

In such a situation, you need a leader with nerves of steel. If anyone fits the bill, it's Sharon. For good or for bad, he's no pushover. If the door is closed, he won't give up until he finds a way to open it. Now is the time to tell all vacillating politicians in this country, whatever party they hail from - Labor, Shas or Likud - or whoever they may be, including Sarid and Beilin: Leave your account books at home.

With all the mayhem and madness, Sharon is still the only one who can pull off disengagement from Gaza, which most of the people in this country want. Don't let him fall.