On June 5, the world will commemorate the 40th anniversary of Israel's triumph in the Six-Day War. The outcome was one of the most convincing conventional military victories of the 20th century, one that removed the threat of annihilation from the Jewish State for the next four decades.

The Existential Threat
In May 1967, Egypt's dictator, Gamal Abdel Nasser, and the leaders of Syria, apparently misled by carefully-fed Soviet disinformation, mobilized their armies and kicked U.N. peacekeepers out of Sinai. Nasser proclaimed that "the Jews would be thrown into the Mediterranean." "Our basic objective will be to destroy Israel," he vowed during a speech on May 26, 1967.

Nasser also closed the Straits of Tiran in the Red Sea, cutting Israel's maritime link to the Far East and Africa-a casus belli under international law. Jordan joined the pending attack, while Iraq, Saudi Arabia, Kuwait, and Algeria also contributed troops and arms. The shadow of the Holocaust, which had occurred just over 20 years earlier, descended on Israel.

The Keys to Victory
The key to Israel's victory was recognition that the survival of the nation was at stake. Both the people and its leaders had no choice but to become heroes overnight, leading to a unified government and full mobilization of the state and the people.

A generation of brilliant generals, led by Defense Minister Moshe Dayan, was in charge of the military, ably supported by Ezer Weizmann, former Israeli Air Force (IAF) commander and Deputy Chief of Staff. Weizmann, the future President of Israel, and his successor, General Moredchai Hod, took a large risk by throwing its well-trained, 200-plane-strong IAF against the Russian-trained Egyptian Air Force. The IAF, outnumbered three to one, eviscerated the Egyptian Air Force in the first 45 minutes of the war by attacking it on the airfields and destroying the runways.

The complete air superiority of the IAF and the dogged implementation of a daring battle plan designed by then-Southern front commander Yeshayahu Gavish were also key to the victory in Sinai.

Meticulous intelligence work by the Mossad, the foreign intelligence service led by General Meir Amit, and by military intelligence, AMAN, were also vital to attaining victory. Nasser's army in Sinai was decimated.

The Jordanians, occupying Judea and Samaria (the West Bank) and East Jerusalem, and the Syrians, lodged in the escarpments of the Golan Heights, were beaten within
days.

The diplomatic front was different from today. Despite blood-curdling threats by the Arab states, Israel had world public opinion largely on its side. The victory allowed Israel to govern Jerusalem once again, realizing the dream expressed in Jewish daily prayers during almost 2,000 years of exile.

A 2,000-Year-Old Dream Comes True
The Temple Mount, on which Solomon's Temple was built, and the Second Temple, restored after the Babylonian exile, returned to Jewish sovereignty. So did the Western Wall, the most sacred site in Judaism. Israel gained control of biblical towns such as Hebron, the burial place of the biblical Patriarchs; Bethlehem; Shilo; and Shechem (Nablus). Israeli victories in the Six-Day War and in the Yom Kippur War (the failed Аrab attempt at a rematch in 1973) allowed the Jewish State to sign peace treaties with Egypt in 1979 and Jordan  in1994.

Forty years later, however, Israel's existence is being challenged again. Now more than ever, Israel is the proverbial canary in the coal mine of the Middle East, the litmus test of Arab and Muslim attitudes toward the world beyond the Land of Islam.

The New Existential Threat
Today the threat is not only Arab but also Iranian; not secular nationalism and pan-Arabism, but Islamist. It is both extremist Shi'a-as expressed by Iran and Hezbollah-and militant Sunni-articulated by Hamas, Islamic Jihad, Moslem Brotherhood, and increasingly, al-Qaeda-affiliated organizations in Gaza and Lebanon.

Forty years ago, the threat was conventional. Today, Israel and the United States lack strategy and doctrine to defeat the whole spectrum of threats: the suicide bombings and Qassam rockets of Hamas and Fatah, improvised explosive devices in Iraq, and the Iranian-supplied, short-range Katyusha rockets of Hezbollah. The threat is also unconventional-from Syrian rockets armed with chemical weapons to the Iranian nuclear weapons program. It is not the "Israeli occupation" but the rise of extremist Islamist forces which constitutes the biggest threat to global security and Middle East stability.

Israeli, European, and American policymakers and generals still think in terms of nation-states and conventional armies, whereas the global jihad movement-its political leaders, paymasters, recruiters, and propagandists-recognize no national borders.

One Lesson Forgotten
Israel also appears to have forgotten the lesson that in the Middle East, one can negotiate only from a position of clear strength. Unilaterally pulling out of Lebanon in 2000 and from Gaza in 2005 only increased the terrorists' appetite for blood. Ehud Olmert's proposal to appease Syria by giving up the Golan Heights would be yet another geopolitical catastrophe.

Allowing bloodthirsty terrorist leaders-such as Ahmadinejad, Sheikh Hassan Nasrallah, Hamas's Haled Mashal, or, for that matter, Osama bin Laden-to roam free only delays peace in the Middle East.

The Price of Freedom
The Six-Day War teaches important lessons about preserving freedom. National mobilization and unity in recognition of existential threats lead to victory. Bravery and real leadership, both civilian and military, secure success. Never underestimate the enemy. Intelligence matters-and so do public diplomacy and global information support. Finally, both political and military institutions must recognize the nature of the evolving threat and must devise and implement brave strategies to defeat the implacable enemies of the free world, then and now.

Ariel Cohen, Ph.D., is Senior Research Fellow in Russian and Eurasian Studies and International Energy Security in the Douglas and Sarah Allison Center for Foreign Policy Studies, a division of the Kathryn and Shelby Cullom Davis Institute for International Studies, at The Heritage Foundation.