No sooner had Hamas's delegation set foot on Russian soil Friday than its members took pains to deflate their hosts' claims that dialogue was a means to moderating the Palestinian Authority's new leadership. Hamas's exiled leader Khaled Mashaal didn't beat about the bush. "We will not recognize Israel," he declared. Fellow Hamas official Muhammad Nazal added: "The subject of recognizing Israel is not open for discussion." The Russian invitation to Hamas and the latter's intransigence underscore the emerging clash between two distinctly contradictory approaches to the current situation. One approach - that advocated by the US and Israel and, at least formally by the Quartet as a whole - is isolation. Russia, though a member of the Quartet, surprised the international community by proposing the other: engagement. Both strategies ostensibly aim to change Hamas's positions. Indeed Russian president Vladimir Putin stressed last month that his foreign ministry officials will seek to persuade Hamas to submit to the Quartet's conditions - recognizing Israel's right to exist, renouncing and combating terrorism and violence and accepting all previous PA undertakings. Now we have the first results of the experiment: engagement doesn't work. The Russians, and other governments that have invited Hamas for talks, such as South Africa, Turkey, and Venezuela, would no doubt argue that this approach simply should be tried for longer, and that patience will be rewarded. Patience is no doubt necessary, but which approach has a better chance of success? It could be reasonably argued that Hamas will not transform itself and abandon its raison d'etre no matter what pressure is put upon it. What is not reasonable to argue is that no pressure at all - simply accepting Hamas as is - has a chance of changing Hamas's positions. The engagement approach should be recognized for what it is: not a legitimate strategy with a realistic chance of success, but a way of claiming to pursue a goal that has in truth been abandoned. But what of the contention that isolation is also a hopeless policy, both in the sense that it has no chance of changing Hamas and that it abandons the hope for peace? The truth is that there are no guarantees that a policy of isolation, even one unified enough to threaten Hamas's grip on power, will induce the desired transformation. The Palestinians have repeatedly chosen courses of action that clearly contradict their interests. Abba Eban's observation about their tendency to "never miss an opportunity to miss an opportunity" stands as true today as it ever did. But the international community's requirements of Hamas, and by extension of the Palestinians, are not arbitrary stipulations. They are the essence of the quest for peace. The rise of Hamas illustrates what has always been true but seldom recognized: that the root cause of the Arab-Israeli conflict is not the nature of Israel or its policies, but the fact of our existence. If the international community gives up on its demands and accepts Hamas as it is, it will be giving up on peace. It will have returned to the failed policy of ignoring Hamas's genocidal goals and tactics - which is what destroying Israel through terrorism means - in the belief that this or that Israeli withdrawal will solve the problem. Unfortunately we have seen the opposite to be the case: as Israelis seem poised to overwhelmingly elect parties that support a two-state solution, the Palestinians have chosen Hamas. It is precisely those who believe in the inherent moderation of the Palestinian people who should most strongly back a policy of isolating Hamas. If the international community decided to tolerate Hamas, it would be compounding its error of for years propping up a corrupt PA despite its refusal to abide by its commitments regarding both the rule of law and terrorism. Even if Hamas had not risen to power, the policy of refusing to hold Palestinians accountable had gone bankrupt and had to be changed to revive any hope for peace. In this context, the rise of Hamas is actually an opportunity to correct past mistakes. If the Palestinian people are indeed ready to abandon terrorism and draw a peaceful border with Israel - as their previous choice of Mahmoud Abbas could be seen to indicate - forcing Hamas to accept that policy is to take the Palestinian people's side. Such an approach may not hold the promise of quick results, but it is the only one with a chance of working.