History will note the premiership of Ariel Sharon as the pivotal moment when Israel decided that ending control over the Palestinians was in its existential interest, and took dramatic unilateral action to implement that decision. Disengagement, defeating terrorism and building the security fence have been essential in cutting the Gordian knot between Israel's interests and Palestinian political will and capacity. Negotiation, by contrast, is what unites Sharon's critics. From the Left, Yossi Beilin contends that, since the contours of a final status agreement are known, all that remains is to seal the deal. From the Right, Binyamin Netanyahu advocates the logic of the quid pro quo - "if they give, they'll receive" - implying that time is on Israel's side and the ball is in the Palestinian court. But what if the Palestinians are unwilling or unable to end the conflict? What if they don't "give"? Does that mean Israel will stay in the Palestinian areas indefinitely? Though a regional economic and military superpower, in the world of negotiations Israel had been powerless to address the existential threat it had identified. It was the Palestinians, rather, who had the ability to hold Israel hostage by refusing to agree to any settlement that would end their own occupation. History teaches that a stand-off between "occupier" and "occupied" leads to one outcome: liberation and independence. The Palestinians had time, or at least they used to have it until disengagement. Before the summer of 2005, the Israeli public had two choices before it, both of which depended on negotiations. The first was the pursuit of a final-status accord in which failure to reach agreement on the Temple Mount meant no agreements on economics, security or civic issues. The other option was the road map - a sequenced approach to establish a Palestinian state in provisional borders before a Permanent Status Agreement. Over the past few years, both tracks seemed doomed to deadlock. Profound disagreements on content and structure, the weakness of the Israeli political system, and a dysfunctional Palestinian leadership all blocked a permanent accord. The road map also seemed stuck due to disagreements on the entry point, and on each of its phases. It is these perceived deadlocks that have legitimized unilateralism and transformed it into a compelling option. The powerful logic of disengagement is that it has partially ended Israeli control over the Palestinians without their consent, but with US endorsement and in coordination with other relevant third parties. This combination has galvanized international support and disarmed Palestinian opposition. THE SECRET, however, of the successful execution of the Gaza disengagement - and an essential part of its logic - relates to Israel's internal politics. Sharon succeeded in bridging the gap between the requisites of a deal with the Palestinians, on the one hand, and the positions and perceptions of the Israeli mainstream, on the other. Sharon decided to focus on the latter, designing disengagement around the "stomach" of the Israeli public. He understood that support for disengagement would be solid because it is perceived as good for Israel even under fire and with no reciprocity. At the same time, Sharon understood that expanding disengagement too far might compromise public support, so he rejected all temptations and pressures to go further or to negotiate. Sharon assumed that politicians would follow the public. He was right. Disengagement was just the first step of Sharon's strategy. His public statements reveal that he was seeking to create a new Israeli-Palestinian equilibrium based on five tenets: ending Israeli control over the Palestinians with international recognition; creating a Palestinian state in provisional borders that will assume control over its territory and population; securing Israeli control over issues critical to its national security, such as the airspace; designing a new framework for reaching permanent status; and beginning to permanently resolve the refugee issue within the Palestinian state. In the apparent absence of a Palestinian "partner," Sharon's strategy would have required further unilateral withdrawals. The logic of disengagement may have not been exhausted. For example, under the new unilateralist paradigm, Israel can dismantle isolated settlements and illegal outposts or transfer the Palestinian neighborhoods in north Jerusalem - which are already outside the security fence - to the PA. More powers and responsibilities could be transferred to the PA in the spheres of economics, civic affairs or diplomacy. Eventually, Israel might consider recognizing the PA as a state. Palestinian statehood has been incorporated into Sharon's strategy for years. His statements suggest that he may have perceived Palestinian statehood to be as much an opportunity as it was a threat. For example, he assumed that the existence of a Palestinian state would mean that Palestinians could no longer claim to be refugees and that UNRWA's powers could be turned over to the Palestinian government. A Palestinian state, furthermore, is a precondition for restructuring the approach toward final status. Once a Palestinian state exists, Israel would be able to negotiate multiple state-to-state agreements focused primarily on the West Bank and Gaza. These agreements might be made piecemeal, rather than holding all progress hostage to a potential comprehensive accord. SHARON'S LEGACY is not limited to his strategy to end control over Palestinians, which enhanced unity within Israel and the Jewish world, boosted Israel's international standing and offered the only feasible path out of the deadlock. It is also a legacy of pragmatism and realism focused on the pillars of our national security: preserving a Jewish majority, fighting the nuclear threat, securing personal safety, and bolstering our alliance with America. This is the consensus agenda that Sharon galvanized into a political force that will transcend his tenure. By taking the excruciating and courageous step of distancing himself from political and personal friends and allies as well as, ultimately, from his own party, Sharon plunged himself and the nation through two years of constant crisis management toward disengagement and beyond. His was an outstanding display of leadership, political skills and executive management. This performance extended beyond security to socioeconomics as well. Many may challenge the logic of disengagement or the wisdom of Sharon's socioeconomic policies. Few would contest that a large part of his legacy was the capacity to get things done. The writer is the founder and president of the Re'ut Institute (www.reut-institute.org) and was a member of the Israeli delegation to the 2000 Camp David Summit.