Since the deadly 1929 riots, the struggle over Jerusalem has been at the core of the Arab-Israeli conflict, and, as recent events show, nothing has changed. For the Palestinians and their supporters, any Jewish presence in Jerusalem that is not under Arab control is not only unacceptable, but seen as threatening. And every ancient text, archeological find or property claim that validates the 3,000-year Jewish historical and religious heritage in this most sacred of cities, is angrily rejected as "Judaization." These allegations are used to promote and justify violent attacks, from rock-throwing to mass terror. In the language of game theory, Jerusalem - more than any other dimension of this extremely complex conflict - has been and remains a zero-sum situation. This means any concessions from one side are necessarily victories for the other, making compromise not only difficult but inconceivable. In a zero-sum world, there is no room for different voices and opinions, and compromise based on acceptance of different perspectives is impossible. Thus, for the Arabs, recognition of the history and legitimacy of Jewish claims is a threat to their own narrative and legitimacy, particularly for the Muslims. Trapped in this social rubric, shared control based on mutual acceptance and recognition, as imagined in many peace programs, is impossible. THE LATEST round of Arab violence in Jerusalem, fanned by competition for the prestige gained by the most extreme voices highlights the lack of movement on this core identity issue. For most Palestinians, and indeed, much of the surrounding Arab and Islamic world, there is absolutely no readiness to acknowledge even the most basic historical facts that would require compromise on Jerusalem. In July 2000 at the Camp David summit, Yasser Arafat shocked and angered president Bill Clinton by rejecting any discussion of joint control over Jerusalem. Clinton and his advisers, who had been shepherding the Oslo negotiations for many years, should not have been surprised. Arafat's position reflected and reinforced the dominant view of most Arabs and Muslims. Similarly, the efforts by NGO officials who claim to promote mutual acceptance and compromise on Jerusalem, and are funded by European governments, have sharpened the zero-sum framework. For example, political NGOs like Ir Amim only criticize Israel. The film Jerusalem Moments was described in The Jerusalem Post as an "incendiary Palestinian propaganda onslaught" and "an exercise in the bludgeoning documentation of Palestinian victimhood and of allegedly mindless Israeli cruelty and aggression." For Palestinians, support from these Israeli NGOs is used to reinforce the zero-sum position, and reject compromise. (Ir Amim and similar political NGOs also address foreigners, including journalists and diplomats, and take groups on highly distorted "educational" tours of Jerusalem and the security barrier in the effort to press their positions.) By their nature, zero-sum situations are not confined to one side of the conflict; when one participant rejects all compromise, the others are forced into the same strategy. Thus, the Palestinian and Arab position that erases all Jewish links to Jerusalem leads to escalation of Jewish defensive moves, designed to prevent a return to the 1948-1967 situation of total exclusion and desecration. For Jews, the total failure to implement the terms of the 1949 armistice agreement guaranteeing, on paper, free access to sacred sites, remains a traumatic memory. Between 1948 and 1967, when the Old City was under Arab occupation, the Jewish Quarter, including synagogues and cemeteries, was systematically desecrated, and the "international community" did nothing to enforce the agreement. Since then, the periodic waves of Arab violence in Jerusalem revive the concerns that agreements based on shared sovereignty or "international control" would lead to the same unacceptable situation. With no sign of movement towards a realistic compromise, Jewish Israelis worry that unless their presence in the city is strengthened, they will eventually be pushed out, yet again. In the zero-sum cycle, the Jewish responses to this history and ongoing threats are denounced by the Palestinians and their supporters as more "occupation" and "Judaization" of Jerusalem. This feeds the escalating violence and reinforces the sense that there is no sense in talking, as no one is listening or willing to compromise. TO MOVE towards even minimal mutual understanding that can contain and prevent outbreaks of violence, the first goal must be to open Palestinian and Arab society to hearing the Jewish version. This would allow for the transition from the zero-sum black-and-white conflict framework to what is known as a "win-win" framework, which allows for coexistence and equality, despite basic differences in narrative and ideology. This is where the various would-be peacemakers and NGO funders, particularly from European governments, should put their money and focus their activities. As long as the Arab and Muslim position slams the door to block Jewish history, Jerusalem will remain a battleground in which the Jewish nation will have no choice but to use force when necessary to defends these rights. The writer heads NGO Monitor and is on the political science faculty of Bar-Ilan University.