The bitter opposition to last year's unilateral disengagement from the Gaza Strip - talk of civil war was in the air - can be partly attributed to the fact that it was Prime Minister Ariel Sharon who ordered the evacuations. For the previous two decades Sharon had been the foremost political and military leader facilitating the establishment of those very settlements. In many cases he personally persuaded Israelis to "grab the hilltops." Whether as minister of agriculture, defense, development and infrastructure or, finally, prime minister - one could always think of him as "godfather of the settlements." Sharon never admitted that it had all been a mistake, gargantuan or otherwise. His best excuse might have been that he was only one of an illustrious list of Israeli leaders from both major parties - Moshe Dayan, Yigal Allon and Menachem Begin, for instance - who saw a settlement presence in the very heart of the Palestinian population in Gaza as essential for Israel's defense. It is to Sharon's great credit that he was capable of changing his mind when new facts required it, even at very great personal and public cost. The greatest damage done by that unexplained change of mind was to shore up the thesis that Israel's entire settlement policy following the Six Day War had been one colossal mistake. It is a typical human error to assume that an admitted mistake in one part of a larger policy necessarily presumes that the entire policy had been mistaken. Not so - not in regard to the Golan Heights, or the Jordan Rift Valley, or to parts of greater Jerusalem and the West Bank. SOME TIME ago I wrote an article in this newspaper asserting that I, too, had been a settler, a mitnahel. I became one when I moved into the new post-Six Day War neighborhood of French Hill, very much on the other side of the Green Line in Jerusalem, and lived there for the next 27 years. The point of that article was that what constituted a legitimate settlement depended primarily on the ability to persuade the outside world of Israel's real security needs, and on persuading a sufficiently large number of Israelis to move into those settlements and consider them home. Home is what individuals, families and mobilized nations are ready to fight for against outside challengers. In that regard French Hill, as well as Ramat Eshkol, Ramot Allon, East Talpiot and Gilo, and latterly Har Homa, have long been beyond such challenges. Those who argue against these Jerusalem "settlements" being annexed to Israel are often the same critics as those opposed to Israel's very existence. WE ARE now in the midst of a process of dividing the West Bank into "ours" and "theirs," on either side of the security barrier. The barrier is going up steadily, albeit with a lot of foot-dragging. Not only is it essential that we end that procrastination, it is even more important that we take steps on the ground to ensure that the Golan Heights and the Jordan Valley, which are of extraordinary security importance, remain as permanently Israeli as the Jerusalem ring of neighborhoods referred to above. Sharon, a masterful military tactician, is often criticized as being a flop as a strategist. I would suggest that his main failure lay in not implementing his most brilliant strategic conception of the "double column" regarding the future of the territories that fell into Israel's hands in June 1967. He was absolutely right, even before championing greater Jerusalem, in insisting on permanent Israeli control of the Golan Heights and the Jordan Valley. Those two regions even have the advantage of extremely sparse Palestinian populations compared to the teeming Gaza Strip and the mountainous spine of the West Bank. Over a week ago The Jerusalem Post reported Palestinian complaints that the IDF was taking steps meant to curtail the minuscule Palestinian presence in the Jordan Rift Valley. If those reports are true, they should be welcomed as constituting a very belated change in policy. But they are far from enough. Needed is a major beefing up of the Israeli settlement presence in the valley, something that has been sorely neglected because of the settlement movement's misguided prioritizing of Gush Katif and the settlements in the heartland of the West Bank. What makes permanent Israeli possession of the rift valley all the more important now is the recent Hamas electoral victory in the Palestinian territories and developments in the war in Iraq. These developments clearly undermine the cavalier attitude of many Israeli leaders and analysts, who were prepared to assume the disappearance of a postwar Iraq and an independent Palestinian Authority from the list of Israel's mortal enemies. Not only should a newly radicalized Palestine and a postwar Iraq be viewed as enemies of Israel, they must also be considered mortal threats to the Hashemite regime in Jordan and to the still fragile peace we have with Amman. The presence of a hostile Iraqi army on the Jordan River is no longer as unthinkable as it may have been in recent years. The writer is a veteran commentator on Israeli society.