Israel has been unnerved by Egypt's revolution. The reason is simple: it fears for the survival of the 1979 peace treaty - a treaty which by neutralizing Egypt, guaranteed Israel's military dominance over the region for the next three decades.

By removing Egypt -- the strongest and most populous of the Arab countries -- from the Arab line-up, the treaty ruled out any possibility of an Arab coalition that might have contained Israel or restrained its freedom of action. As Israeli Foreign Minister Moshe Dayan remarked at the time: "If a wheel is removed, the car will not run again."

Western commentators routinely describe the treaty as a ‘pillar of regional stability,' a ‘keystone of Middle East diplomacy,' a ‘centerpiece of America's diplomacy' in the Arab and Muslim world. This is certainly how Israel and its American friends have seen it.

But for most Arabs, it has been a disaster. Far from providing stability, it exposed them to Israeli power. Far from bringing peace, the treaty ensured an absence of peace, since a dominant Israel saw no need to compose or compromise with Syria or the Palestinians.

Instead, the treaty opened the way for Israeli invasions, occupations and massacres in Lebanon and the Palestinian territories, for strikes against Iraqi and Syrian nuclear sites, for brazen threats against Iran, for the 44-year occupation of the West Bank and the cruel blockade of Gaza, and for the pursuit of a ‘Greater Israel' agenda by fanatical Jewish settlers and religious nationalists.

In turn, Arab dictators, invoking the challenge they faced from an aggressive and expansionist Israel, were able to justify the need to maintain tight control over their populations by means of harsh security measures.

One way and another, the Israeli-Egyptian treaty has contributed hugely to the dangerous instability and raw nerves which have characterized the Middle East to this day, as well as to the sharpening of popular grievances, and the inevitable explosions which have followed.

Suffice it to say that, emboldened by the treaty, Israel smashed Iraq's Osirak nuclear reactor in 1981 and, the following year, invaded Lebanon in a bid to destroy the PLO, expel Syrian influence and bring Lebanon into Israel's orbit. Israel's 1982 invasion and siege of Beirut killed some 17,000 Lebanese and Palestinians. In an act of great immorality, Israel then provided cover (and arc-lights) to its Maronite allies as they engaged in a two-day slaughter of helpless Palestinians at the Sabra and Shatila refugee camps. Israel remained in occupation of southern Lebanon for the next 18 years, until driven out in 2000 by Hezbollah guerrillas. So much for the peace treaty's contribution to Middle East peace and stability!

The origins of the peace treaty can be traced to the diplomacy of Henry Kissinger, President Nixon's national security adviser at the time of the October War. Committed to protecting Israel but also to pulling Egypt out of the Soviet orbit of influence (and not averse to dressing down the Israeli side when their stubbornness undermined the balancing of these two goals), Kissinger maneuvered Egypt's Anwar al-Sadat out of his alliance with both Syria and the Soviet Union, and towards a cozy relationship with Israel and the United States.

With the 1975 Sinai disengagement agreement, Kissinger removed Egypt from the battlefield - a fateful decision which led directly to the Camp David accords of 1978, and the peace treaty of 1979. Sadat may have hoped for a comprehensive peace, involving the Palestinians and Syria. But he was out-foxed by Israel's Prime Minister Menachem Begin, a Zionist of the Jabotinsky school who was determined to destroy Palestinian nationalism and prevent the return of the West Bank to the Arabs. Begin was happy to return the Sinai to Egypt in order to keep the West Bank.

Weakened at home by pro-Israeli forces, President Jimmy Carter witnessed unhappily the scaling down of his peace effort from its original multilateral aims to a mere bilateral outcome - a separate Israeli-Egyptian peace. At the end of the day, Washington swallowed Israel's argument that the treaty ruled out the threat of a regional war and was therefore in America's interest. Egypt's army was given $1.3 billion annual U.S. subsidy -- not to make it more warlike but, on the contrary, to keep it at peace with Israel.

Defense of the peace treaty remains the prevailing wisdom in Washington. The Obama administration is reported to have told Egypt's military chiefs that they must maintain the treaty. In turn, Egypt's Supreme Military Council has said that Egypt will honor existing treaties. So there will evidently not be any revocation of the treaty. No one in Egypt or in the Arab world favors a return to military action, nor is ready for it. But the treaty may well be put on ice.

We do not yet know the color of the next Egyptian government. In any event, it will be hugely preoccupied with pressing domestic problems for the foreseeable future. But if, as is widely expected, this government will have a strong civilian component drawn from the various strands of the protest movement, adjustments of Egypt's foreign policy must be expected.

It is highly unlikely that Egypt will continue Hosni Mubarak's policy - deeply embarrassing to Egyptian opinion -- of colluding with Israel in the blockade of Gaza. Nor is the new Egypt likely to persist in Mubarak's hostility towards the Islamic Republic of Iran and the two resistance movements, Hamas and Hezbollah. Whether the treaty survives or not, Egypt's alliance with Israel will not be the intimate relationship it was.

The Egyptian revolution is only the latest demonstration of the change in Israel's strategic environment. Israel ‘lost' Iran when the Shah was overthrown in 1979. This was followed by the emergence of a Tehran-Damascus- Hezbollah axis, which has sought to challenge Israel's regional hegemony. Over the past couple of years, Israel has also ‘lost' Turkey, a former ally of real weight. It is now in danger of ‘losing' Egypt. The threat looms of regional isolation.

Moreover, Israel's relentless seizure of Palestinian land on the West Bank and its refusal to engage in serious negotiations with the Palestinians and Syria on the basis of ‘land for peace' have lost it many former supporters in Europe and the United States. It is well aware that it faces a threat of ‘de-legitimization.'

How will Israel react to the Egyptian revolution? Will it move troops to its border with Egypt, strengthen its defenses, desperately seek allies in the Egyptian military junta now temporarily in charge, and plead for still more American aid? Or will it - at long last - make a determined bid to resolve its territorial conflicts with Syria and Lebanon and allow the emergence of an independent Palestinian state with its capital in East Jerusalem?

Israel urgently needs to rethink its security doctrine. This is the clear lesson of the dramatic events in Egypt. Dominating the region by force of arms -- Israel's doctrine since the creation of the state -- is less and less of a viable option. It serves only to arouse ferocious and growing resistance, which must eventually erupt into violence. Israel needs a revolution in its security thinking, but of this there is as yet no sign.

Only peace, not arms, can guarantee Israel's long-term security.

Patrick Seale is a British writer, who specializes in Middle East affairs. His latest book is The Struggle for Arab Independence: Riad el-Solh and the Makers of the Modern Middle East.