The nuclear tests by India and Pakistan have left Israel alone in the world as a country that is widely believed to have nuclear weapons but that has not acknowledged it does. For now, Israel is apparently happy to leave it that way.

The reaction in Israeli Prime Minister Benjamin Netanyahu's office to the Indian and Pakistani tests has been to reiterate the standard Israeli response to any inquiry about its nuclear program - "We will not be the first to introduce nuclear weapons into the Middle East" - and to direct attention to Iran, which is believed to be working on a nuclear weapon.There is the sense that the "nuclear ambiguity" introduced by the construction of the Dimona nuclear reactor in the Negev in the 1950s and 1960s has served Israel well over the last three decades in "creating fear without creating anger," as the policy has been defined, and is in no need of change.

Israel's possession of nuclear weapons has been widely suspected for decades, because the threat of such a weapon was presumed to be the purpose behind the Dimona nuclear plant. But by refusing to acknowledge them, Israel has spared the United States the need to impose sanctions under the Nuclear Non-Proliferation Treaty.

"We managed to create sufficient suspicion for there to be deterrent, without having gotten to a status of clarity which would behoove sanctions against us," Shi-mon Peres, who as a young official was instrumental in building Dimona, said in a recent interview.

In December 1995, Peres, then prime minister, came closest of any Israeli official to acknowledging that Israel had the bomb and suggested that it could get rid of it once it was at peace with all its neighbors.

"If there will be a regional peace, I think we can make the Middle East free of the nuclear threat," Peres said then.

In a recent television interview, Peres said, "I built Dimona in order to get to Oslo, not Hiroshima," referring to the Israeli-Palestinian peace accord worked out in Norway. The purpose of letting the Arabs believe that Israel could not be defeated in war, he said, was to persuade them to make peace.

The bomb built by the Muslim nation of Pakistan, Peres argued, could change that.