To understand what is happening between Israel and the Palestinians now, it is important to understand what happened in the Middle East war of 1967 - a subject of much debate among historians. The BBC Middle East editor Jeremy Bowen, who presented the Radio 4 series Six Days That Changed the Middle East, here gives his own assessment.
It took only six days for Israel to smash the armed forces of Egypt, Jordan and Syria but over the last 40 years, the legacy of the war has shaped the conflict into what it is today.
The war made 250,000 more Palestinians - and more than 100,000 Syrians - into refugees. No peace is possible in the Middle East without solving their problems.
Israel became an occupier.
It captured the Sinai Peninsula and the Gaza Strip from Egypt, the Golan Heights from Syria, and the West Bank and East Jerusalem from Jordan.
Israel had another, very serious, war with Syria and Egypt in 1973, but increasingly the main Arab thrust against Israel came from Palestinian groups, led by Yasser Arafat's PLO.
For Palestinians, the lesson of the humiliating defeat suffered by the Arab frontline states in 1967 was that no-one else was going to do their fighting for them.
The failure of Arab nationalism in 1967 was also a major factor in the early development of political Islam. The mosques began providing the answers to questions that the secular strongmen could not convincingly answer.
Spoiling for a fight
While historians hold different views on the 1967 war, one school of thought is that it is a myth to suggest the Israeli David slew the Arab Goliath, and that it is more accurate to say there were two Goliaths in the Middle East. The Arabs, taken together, had big armed forces, but they were not ready for combat.
The Jewish Goliath had never been in better shape, and knew it, or rather its leaders did. In 1967 Israel was a fortress society in a way that it is no longer. There was no television, and generals and politicians did not leak their business to their favourite journalists as they do today.
Israeli civilians, especially in the crisis that led to war, were left to their own fears, which for many people were considerable.
The Jewish state was only 19 years old and the youngest survivors of the Holocaust were barely in their 20s. Egyptian leader Gamal Abdul Nasser's radio station Voice of the Arabs fed their anxieties by broadcasting bloodcurdling threats.
Its chief announcer, Ahmed Said, had the best known voice in the Arab world in the 1960s after Nasser himself and the legendary diva, Umm Kulthum.
Said was famous for lines like this: "We have nothing for Israel except war - comprehensive war... marching against its gangs, destroying and putting an end to the whole Zionist existence... every one of the 100 million Arabs has been living for the past 19 years on one hope - to live to die on the day that Israel is liquidated."
No wonder many Israelis and their friends and relations abroad were scared stiff.
Reports of what Said was saying, and even the broken Hebrew of broadcasts beamed directly into Israel from Cairo, convinced many Israeli civilians that if they were facing enemies that were prepared to annihilate them, then they needed to fight, and fight hard.
The problem for the Arabs was they believed Ahmed Said and his colleagues too, and convinced themselves that an easy victory was coming.
The generals' hour
Israel's generals were not taken in. They all knew that the only way that Israel would lose the war would be if the IDF did not turn up.
The Israeli generals... had been training to finish the unfinished business of Israel's independence war of 1948 - the capture of East Jerusalem - for most of their careers
So did King Hussein of Jordan, and most of the Egyptian generals - with the exception of the inept and corrupt commander-in-chief, Field Marshal Abd al Hakim Amer.
The Israeli Air Force destroyed the Egyptian air force on the ground on the morning of 5 June 1967 in a surprise attack.
In the next five days Israel confirmed the intelligence estimates of the British and the Americans.
Six weeks earlier, the British cabinet's Joint Intelligence Committee had concluded that an Arab victory was "inconceivable."
Around the same time, the US Joint Chiefs of Staff said Israel would be "militarily unchallengeable by any combination of Arab states at least during the next five years".
The Israeli generals, hugely self-confident, mainly sabras (native-born Israeli Jews) in their late 30s and early 40s, had been training to finish the unfinished business of Israel's independence war of 1948 - the capture of East Jerusalem - for most of their careers.
When their political leaders, most of whom were cautious immigrants at least 20 years older, tried to use diplomacy to end the crisis that led to war, the top brass were beside themselves with frustration.
They believed that delay meant more casualties, and the unnecessary postponement of the inevitable war and inevitable victory for which they had been preparing.
Nasser's motives for risking war in 1967 are still debated.
Another explanation is that Nasser was prepared to take Israel to the brink to reinforce his position as an Arab hero
Two Israeli historians have recently suggested that he was egged on by the Soviet Union, which wanted Egypt to destroy Israel's nuclear weapons programme at Dimona.
Another explanation is that Nasser was prepared to take Israel to the brink to reinforce his position as an Arab hero.
If it went over the brink, he assumed the superpowers would rescue him and deliver a political victory, as they had in the Suez war of 1956.
When victory came, Israeli civilians, who had never been told how strong Israel was, believed that they had escaped a terrible fate.
David Rubinger, the Israeli photographer who took the most iconic pictures of the war, was with IDF paratroopers when they captured the Western Wall, and was swept up in the mood:
"We were all crying. It wasn't religious weeping. It was relief. We had felt doomed, sentenced to death. Then someone took off the noose and said you're not just free, you're king. It seemed like a miracle."
The conviction that it was a miracle, that God saved the Jewish people and reunited them with their historic homeland in Judea and Samaria, is still the driving force behind Israeli religious nationalism.
When the messianic moment of victory combined with the tendency within Zionism to push out the frontier, the result was the settlement movement.
Israel's reward, apart from victory itself, was a new strategic relationship with the United States.
Nearly half a million Jews have settled in the West Bank since 1967
Yet even before the fighting ended, as Israel completed its capture of Jerusalem and the West Bank, President Lyndon Baines Johnson, one of the staunchest friends Israel has ever had in the White House, warned that by the time the Americans had finished with all the "festering problems", they were going to "wish the war had never happened".
Four days after the war ended, US Secretary of State Dean Rusk warned that if Israel held on to the West Bank, Palestinians would spend the rest of the century trying to get it back.
Forty years on, Israel has settled around 450,000 people on land occupied in 1967, in defiance of almost all countries' interpretation of international law except its own.
The settlers are protected by all the resources of the state, including the IDF, from a rebellious subject people, many of whom believe that ruthless violence targeted at civilians as well as soldiers is a legitimate response to occupation.
For Palestinians, the settlements are a catastrophe, made worse every day by the fact that they are expanding fast.
After 40 years as an occupier, Israel can no longer count on the international support it had in 1967.
The settlers see their presence as a national asset, necessity and obligation, but many other Israelis, to varying degrees, believe the settlements, and all the other legacies of 1967 that have deepened the conflict with the Palestinians, are a national disaster.
"The tail started wagging the dog," David Rubinger complains bitterly. "Now the tail is so strong the dog can't move."
Amendments were made to this article on 15 and 16 April and on 13 October 2009 following findings by the Editorial Standards Committee of the BBC Trust, published on 15 April 2009. The Trust said the language used by Jeremy Bowen in the article had in some cases not been sufficiently clear and precise to meet the corporation's standards on accuracy. It also upheld one complaint and partially upheld another complaint that the article breached guidelines on impartiality.
Full details are posted