On January 9, President George W. Bush is scheduled to make his first visit to Israel since taking office in 2001, and while he will get a warm reception, it will be mixed with the impact of tensions in the relationship. In particular, the "December surprise," resulting from the publication of the US National Intelligence Estimate (NIE) summary report on Iran's nuclear weapons program, reminded Israelis of the limits of American security guarantees and strategic cooperation. Other sources of stress come from differences over renewed efforts to forge an agreement with the Palestinian Authority headed by Mahmoud Abbas, and, in this context, the status of the Israeli anti-terror measures. In addition, the overall decline of US influence, as reflected in Iraq, the return of Russia as a world power, the chaos in Pakistan, and other developments are forcing Israeli security planners to review the degree of security dependence on Washington. For Israel, the Iranian nuclear weapons program is the most acute strategic threat, and the sudden shift in US policy as reflected in the NIE report - of which only a summary was declassified - was a major shock. The summary, and the subsequent headlines, declared: "We judge with high confidence that in fall 2003, Teheran halted its nuclear weapons program." While a footnote and subsequent paragraphs explained that this assessment was limited to only one aspect of the Iranian program - "weaponization" - and that the other more important aspects, including uranium enrichment, were continuing, the headline took the urgency, and the justification, out of the US-led coalition on Iran. THESE developments abruptly ended 15 years of Israeli policy based on working with the international coalition to pressure Iran to drop its nuclear weapons program through sanctions and the threat of military action, if necessary. Within two weeks following publication of the NIE report, the momentum of the sanctions regime, built up slowly over recent years, was suddenly reversed. In short order, China and Malaysia signed contracts on energy development and supply with Iran, and Russia, which had withheld the fuel rods for the Bushehr nuclear reactor for at least one year, quickly dispatched two shipments. In parallel, the leaders of the Sunni Arab component of the coalition to prevent Iran from becoming a nuclear weapons state also concluded that the US had changed course. Egypt moved to improve relations with Iran, and Saudi Arabia welcomed Iranian President Mahmoud Ahmadinejad to Mecca for the haj. THE THREAT of a US-led military attack on Iranian nuclear installations had become extremely unlikely. This was perhaps the main purpose of the officials who wrote the published summary - to make it all but impossible for President Bush to order an attack on Iran's nuclear facilities in the last year of his administration. Despite the central importance of these issues, the years of strategic coordination meetings, and the repeated American assurances, Israeli policy-makers were apparently not consulted on the decision to release the NIE report, the timing, or the very contentious wording. Israel could do nothing as the US crippled these two primary sources of pressure, which had contributed to the Iranian decision to close (or hide) the blatant aspects of nuclear weapons development in 2003. As a result, although President Bush, Secretary of State Condoleezza Rice, and others have put Palestinian-Israel peace efforts after the Annapolis meeting on the top of their agenda for this trip, the primary Israeli issue is Iran. On his way to the US at the end of November, Prime Minister Ehud Olmert explained the logic of the "Annapolis process" in terms of the coalition to stop Iran, and the need to involve the Saudis and other Arab states in this coalition by demonstrating movement and hope on the Palestinian track. But two weeks after Annapolis, with the release of the NIE report, this rationale became irrelevant. WITHOUT a serious prospect of stopping Iran through sanctions or US-led military action, the basis for changes in Israeli policy that involve security risks in order to help the Palestinian Authority also becomes less compelling. In anticipation of pressure on Israel to ease movement for Palestinians as part of the massive economic development plan, and Secretary of State Rice's statements that echo traditional Arab and European emphasis on Palestinian victimization, Defense Minister Ehud Barak declared that Israel cannot - and will not - remove checkpoints that are vital to preventing Palestinian terrorism. The murder of two Israelis at the end of December by Fatah gunmen, connected with the same security forces that are armed and trained as part of the Annapolis framework promoting Palestinian statehood, was a stark reminder of the risks involved for Israel, and the policy differences with the US. FOR THESE reasons, proposals that the Bush visit be accompanied by discussions of a US-Israel defense treaty are unrealistic. A treaty would limit Israel's freedom of action, and while the assistance provided by the US for 40 years may be unprecedented, it cannot substitute for an independent Israeli military capability when vital interests are at stake. The political maneuvering in Washington that apparently led to the wording of the NIE, and the differences emerging over the relaxing of security measures related to hopes for a breakthrough in negotiations with the Palestinians, are pointed reminders of the limits of even the closest of alliances between sovereign nations. The writer is the head of the Political Studies Department at Bar-Ilan University, a fellow of the Jerusalem Center for Public Affairs, and executive director of NGO Monitor.