The world was taken by surprise after Ariel Sharon's snap decision to leave Likud, thereby breaking the mould of Israeli politics, writes Graham Usher The big bang lived up to its name. On Monday 21 November Ariel Sharon shook the foundations of Israeli politics by quitting Israel's ruling Likud Party while serving as Israel's twice elected prime minister. Compared to this, David Ben-Gurion's decision in the 1960s to leave the Labour Party he had founded was a blip on the Richter scale. Sharon's, by contrast, was a "tsunami", said Israeli analyst Hannan Cystal. And its waves will not only engulf Israel's political landscape but also that of the four million Palestinians under Tel Aviv's charge, whether in Israel or the occupied territories. For some -- especially on Israel's vapid left -- the move, on the heels of the disengagement from Gaza, marks another stage in Sharon's De Gaulle-like transformation, readying to make peace where once he waged war. For others -- including the vast majority of Palestinians -- the two gambits mark less a new Sharon than the latest reincarnations of the old, readying to determine Israel's final borders in line with colonial ambitions rather than international law, or even imbalanced, bilateral negotiations. Sharon's decision followed a weekend of fervid speculation over whether he would leave Likud. By Sunday midnight he had decided. The next morning he went to Moshe Katsav, requesting the Israeli president dissolve parliament "since a majority of the Knesset opposes the government, making it impossible for the government to function properly". New elections will likely be held in March 2006. Later that day Sharon addressed the nation, laying out the reasons for abandoning a party that he, in 1973, had helped create. "The Likud in its present configuration cannot lead the nation to its goals," he said. "I founded Likud to give hope to Israel. But that hope is no longer there. If I had stayed, I probably could have won the primaries and led the Likud to victory in the next election. [But] staying in Likud would have meant wasting time with politics rather than working for the good of the nation. And I prefer the good of the nation over comfort and ease." He then went on to describe the "new, national, liberal party" he would form to reach those goals. "It will be a new home for all the Israelis who want to act responsibly and with faith for the country, and realise the Zionist vision." Its primary aim would be to "lay the foundation for a peace agreement wherein the country's permanent borders will be determined, while insisting on the dismantling of the [Palestinian and Arab] terror organisations". This, he continued, would entail "no additional disengagement [from the West Bank]" but rather "a continuation of the political process in accordance with the roadmap". It was also clear that "the big settlement blocs [in the West Bank] will remain always in Israel's hands", though "in the discussion on the permanent status borders it can be assumed that some of the settlements won't be able to remain". According to confidantes quoted in the Israeli press, there were two reasons behind Sharon's decision to bolt. One -- acknowledged publicly -- was that he had simply lost the trust of his party. This did not necessarily mean he had lost the leadership. It simply meant, post-elections, Sharon would not have been able to form the government or coalition he desired. It would have also meant the elections' timing would have been hostage to Likud's preferences rather than Sharon's. The second reason was the shock victory of Amir Peretz as Labour Party leader and its decision, on 20 November, to withdraw from government. Without Shimon Peres at the head of a docile "opposition" that would back his every move, Sharon knew now he was faced with a challenger, making him dependent on a right-wing that sought only to shackle him. Will Sharon's enormous gamble pay off? Initial returns suggest yes, with snap polls showing Sharon's "national responsibility" party winning 33 seats in the next parliament as against 26 for Labour and a derisory 12 for Likud, even under the watch of former prime minister, Binyamin Netanyahu (almost certain to be elected Likud's next leader). Some 55 per cent of Israelis said they approved of Sharon's decision to dump Likud. Sharon has also -- as he will have to do -- ruptured Likud, with 14 MPs (out of 40) following him into the new fold, including such prominent ministers as Ehud Olmert at finance and Tzipi Livni at justice. They have been joined by ex-labour party minister, Haim Ramon, patent of the Big Bang theory, who has long argued that Sharon should forge a new centrist party to overcome the "outmoded and debilitating" Likud/Labour divide. The great unknown is Shimon Peres. He apparently is undecided about joining the new order, still sunken in the torpor of his latest defeat by Peretz. Sharon is undecided about having him, unsure whether the grand old man of Israeli politics would be an asset or liability to his new enterprise. Sharon's aides are unequivocal. "We don't want a loser in the party," said one. Still, the risks taken by Sharon's move are enormous. In Israeli politics new parties -- especially high-profile centrist ones -- have the trajectory of shooting stars, dazzling in their birth only to extinguish on landing. Sharon certainly has the bulk of Israeli Jewish opinion behind him but he does not yet have a functioning political machine. And Sharon -- perhaps more than any politician in Israel -- knows that elections are won by organisation, not by opinion polls. Palestinians are once more consigned to the role of extras in their own future. The hope of the leadership is that the upheaval in Israeli politics will somehow translate into a revolution in peacemaking, with final status negotiations to end the occupation that began in 1967 and the conflict that began in 1948. For this they can only look to Peretz and the Labour Party he leads. But here too the new bears an uncanny resemblance to the old. Addressing Labour's Central Committee for the first time as leader, Peretz began what seems to be an inevitable journey from left to centre. "The Arab members of the Knesset say I support keeping Jerusalem united (sic) and that I am against the right of return for Palestinian refugees," he told the delegates. "They are right about this. I support keeping Jerusalem united forever and I am against the right of return to places inside Israel." Even more ominously one of Peretz's first acts as Labour Party leader was to approve one of the last decisions of Labour's housing minister, Yitzak Herzog: the construction of 310 more homes at Maale Adumim, a mammoth settlement whose ongoing expansion will divide the West Bank in two, isolate East Jerusalem and end all prospect of a viable Palestinian state. If this is truly Peretz's vision, he could easily be a partner, a la Peres, in Sharon's next coalition government. He will have ceased being a partner for the Palestinians.