On Oct. 5, Yom Kippur, -- the Day of Atonement and the holiest day of the year for Jewish people -- the armies of Egypt and Syria attacked Israel from two directions and made rapid gains.
According to a former senior U.S. diplomat, by Oct. 8, Israel's northern front commander, Maj. Gen. Yitzak Hoffi, had informed Israeli Defense Minister Moshe Dayan that he couldn't hold out much longer against the 14,000 Syrian tanks rolling through Israeli defenses on the Golan Heights.
The source, speaking on condition of anonymity, said that Dayan was "attacked by acute panic" and declared to advisers: "This is the end of the Third Temple."
But if Israel was to perish, it would take Damascus and Cairo with it.
According to a former senior CIA official, who also spoke on condition of anonymity, Dayan sought an urgent meeting with Prime Minister Golda Meir and secured her authorization to arm 13 intermediate-range Jericho missiles with nuclear warheads. Eight F-4 Phantom fighter aircraft were also to be given nuclear arms, former senior U.S. officials said.
The meeting took place close to "the Bor," Israel's huge underground war complex, these sources said.
The predominant opinion today is that Israeli's first nuclear alert was a bluff, but "an extremely dangerous one," a former senior U.S. State Department official said.
The Israelis demanded an emergency airlift of weapons and spare parts from the United States to support an all-out war effort. And they accused then Secretary of State Henry Kissinger of deliberately withholding the re-supply in order to allow the Arabs to gain ground.
According to a source close to former U.S. Secretary of Defense James Schlesinger, the Israelis were right. Kissinger's strategy was to "let Israel come out ahead, but bleed," the source said.
What followed then was just possibly more frightening than anything else that has happened since World War II, according to former U.S. officials. "Israel played a very, very dangerous game, and we came close to a nuclear war," said a former very senior State Department official with detailed knowledge of the incident.
Over the next 3 days, the launchers were armed at Hirbat Zachariah while the F-4s, on 24-hour alert, based at Tel Nof near Rehovot, were also prepared, according to former senior Pentagon officials.
The initial targets -- these officials said -- included the Syrian and Eygptian military headquarters, which were situated near Damascus and Cairo, respectively.
In those days, Israel's nuclear arsenal was something U.S. diplomats and defense officials were taught not even to mention.
"To talk about Israel having nuclear weapons was a real career-ending move," one source said.
At that time, the Jerichos were deployed inside caves, inside Israeli military air bases that had "huge blast doors," a former senior CIA official recalled Monday.
The missile-launchers were set up on the back of railway cars and could be rolled out, fired, then rolled back and the blast doors closed, this official said. "We thought of deploying the Mark III missile in the same way," he added.
Somehow, an agent in place in Israel alerted the United States of the arming of the Jerichos and on Oct. 12, an SR-71 Blackbird reconnaissance aircraft based at Beale Air Force Base in California took off, refueled off of Rota, Spain, and then flew over Syria, Jordan and Israel.
The plane, able to survey 100,000 square miles of land an hour, spotted the radiation from the missiles, according to a former Pentagon official and others familiar with the incident.
According to this Pentagon source, Israel ordered their F-4s to down the plane, but the Blackbird soared to 85,000 feet, beyond the range of the Israeli fighters.
A former employee of Rockwell International, Richard Freeman, told United Press International that the warhead of the Jericho was developed from the U.S. XW-58 warhead developed for the U.S. Army. It was about 24 inches long and 18 to 20 inches in diameter, weighing 200 pounds.
With an accuracy of 500 to 1,000 meters, the warhead "was designed for air bursts above population centers or massed armor formations," he said. But a former CIA official added: "The thing had a lot of problems with its guidance system, and we weren't sure if deployment was real or just saber-rattling."
Saber-rattling or not, that same day, the United States began a huge airlift to Israel including ammunition, tanks and aircraft. Israel made dramatic battlefield gains on all fronts until an Oct. 14 U.N.-Security Council-approved ceasefire brought the fighting to a halt.
But then Israel's current Prime Minister, Ariel Sharon -- who was at the time a major general commanding a division -- broke the ceasefire and began to encircle the Egyptian Third Army, opening the way to Cairo.
It was the Soviets' turn to panic. According to half a dozen former State Department diplomats, Soviet leader Leonid Brezhnev told the United States he might be forced to send in crack troops to back up Egyptian forces defending Cairo.
There was plenty of intelligence that elite Soviet paratroop units were on alert and moving.
To halt Sharon, Kissinger raised the state of alert of all U.S. defense forces worldwide. Called DefCons, for defense condition, they work in descending order from DefCon V to DefCon I, which is war. Kissinger ordered a DefCon III.
According to a former senior State Department official, the decision to move to DefCon III "sent a clear message that Sharon's violation of the ceasefire was dragging us into a conflict with the Soviets and that we had no desire to see the Egyptian Army destroyed."
Israel, which had cancelled its nuclear alert, went on nuclear alert for a second time, until Meir quickly ended the crisis by ordering her army to stop all offensive action against the Egyptians.
But the same State Department official pointed out something that has always been a major deterrent in the Middle East. "If Tel Aviv had used those weapons, most of the fall-out would have blown back on Israel because of the pattern of prevailing winds at the time," he said.
Celebrity Couples of 2014 [PHOTOS]