No longer. Now, most borders have been set, oil fields mapped and reserves accurately estimated - unlike the water resources, which are still often unknown. From Turkey, the southern bastion of Nato, down to Oman, looking out over the Indian Ocean, the countries of the Middle East are worrying today about how they will satisfy the needs of their burgeoning industries, or find drinking water for the extra millions born each year.
All these nations depend on three great river systems, or vast underground aquifers, often of 'fossil water' that cannot be renewed. Few agreements have been reached about how the water should be be shared: upstream, the countries believe that they should control the flow of the rivers, taking what they like; downstream, the states are militarily stronger, and are prepared to challenge this assumption. It is a recipe for confrontation.
And the Palestine-Israel accord, with its prospect of a general peace between Arabs and Israelis, threatens new instability as well as heralding the end of one long dispute. It was the perceived danger Israel posed to all the Arab states that forced their leaders into the mininmal unity they managed to achieve. Faced with what they saw as a common enemy, the Arabs tried to stifle their own disputes. Soon, that constraint may disappear and all the long-suppressed enmities will come into the open.
Already water has played a part in causing wars, altering policies and changing alliances. In 1964, an Arab summit conference decided to divert the headwaters of the Jordan - in effect, depriving Israel of its main supply. Work began despite Israel's warning that it would consider it an infringement of national rights. And though all the work was carried out on Arab or neutral land, battles, air raids and artillery duels occurred.
In the end, Israeli air strikes deep into Syria forced the Arabs to call off their scheme. General Ariel Sharon, later an Israeli defence minister, had no doubt what those skirmishes were all about. 'People generally regard 5 June 1967 as the day the Six-day war began,' he said. 'That is the official date. But, in reality, it started two- and-a-half years earlier, on the day Israel decided to act against the diversion of the Jordan.'
That brief conflict settled nothing, so again in 1973 the Arabs and Israelis went to war. This time, Anwar Sadat of Egypt wanted to use the Arab armies to force Israel to the conference table, and to conclude a lasting peace. He failed then, but, with the help of Henry Kissinger reached a peace treaty with Israel in 1979, after the Camp David meetings.
As the various Israeli-Egyptian committees met to settle the details of the treaty, Israeli delegates suggested that there should be co-operation on water projects. In particular, they wanted about 1 per cent of the Nile flow to be diverted into a pipeline to the Negev.
President Sadat saw this as a basis for regional co-operation, eventually extending the pipeline to Lebanon or Jordan. What he did not realise was the consternation that his ideas would cause at home, where the Nile is held in almost mystical regard; the prime duty of the Egyptian armed forces is to defend and preserve that source of all Egyptian life.
When Egyptian intelligence leaked the information to senior army officers already restive at being forced to make peace with their old enemy, the army rebelled at the prospect of that peace being guaranteed by sharing the Nile with Israel. Plots to oust Mr Sadat were laid, and he was saved only when the CIA learned of them - through an Egyptian officer who defected in London - and warned the Egyptian president.
Amazed that the army could plot against him, Mr Sadat questioned Field Marshal Abdel Halim Abu Ghazala, the defence minister, who said the loyalty of the Egyptian army could not be guaranteed if a coup was mounted 'to stop Israel stealing the Nile'. The president quickly dropped the water-sharing idea.
More recently, Turkey seized an opportunity to demonstrate its ability to control the flow of water to its neighbours, and provoked a remarkable alliance between enemies. In January 1990, it stopped the flow of the Euphrates. Officially, the interruption was to fill the vast new Ataturk Dam; in fact, it was a demonstration to Syria of what might happen if President Hafez al-Assad continued aiding the Kurdish rebels in south- east Anatolia.
Halting the flow of the Euphrates into Syria also brought water shortages in Iraq. Turkish planners thought that would not matter, as Syria and Iraq were bitter enemies. Faced with this common threat, however, old antagonisms were instantly forgotten; the Iraqi and Syrian media united in denouncing Turkey, and military leaders from both countries drew up plans for armed retaliation. After three weeks, the river was allowed to flow as usual, though the stoppage had been planned to last a month.
Trouble between Turkey and Syria over water remains the likeliest prospect today. So far, Turkey has completed only about half of the Gap (South- east Anatolia) project to build dams and reservoirs on the Euphrates. When the Gap is completed, the quantity and quality of water flow to Syria will be affected. And as the whole Western Alliance would be involved by a war between Turkey and Syria, it is no surprise that American and European planners have been working on contingency plans.
When all the Euphrates projects are complete, the Turks intend to harness the Tigris. That will have a direct effect on Iraq, again forcing Syria and Iraq into alliance - though they almost went to war in 1975, when Syria built the Thawrah dam.
President Suleyman Demirel summed up the intransigent attitude of the Turks: 'Neither Syria nor Iraq can lay claim to Turkey's rivers, any more than Ankara could claim their oil . . . We have a right to do anything we like. The water resources are Turkey's, the oil resources are theirs. We don't say we share the oil resources, and they cannot say they share our water resources.'
Syria's answer has been to step up support for the Kurdish fighters of the Kurdistan Workers' Party, spreading devastation in Turkey. Iraq's answer has yet to be made.
The Tigris-Euphrates river basin is the scene not only of a bitter, low-intensity war in eastern Turkey, but also of silent genocide where the two great rivers unite in the Shatt al Arab and discharge themselves into the warm waters of the Gulf. There, Saddam Hussein's engineers have built a 'Third River' to drain the marshes north of Basra, home for 3,000 years to the Marsh Arabs.
Ostensibly an irrigation project, it is really a way of suppressing for ever the last pocket of resistance to President Saddam in the south of the country. The Shia, who answered the call by George Bush for a rebellion in Iraq in 1991, took refuge there when they were defeated, and have been supplied and joined by revolutionary guards and Iraqi dissidents from Iran. Unable to flush them out of their reed- hidden bases, the Iraqis first poisoned the waters, are now draining them - and are destroying a whole people.
Today, Egypt is regarded as the most moderate and helpful of all Middle Eastern countries. But it is as ready as any other country to use force to protect its vital resources. It worries about the dams being built in the Ethiopian highlands, which will affect the flow of the Nile, and about grandiose plans for a canal that could tap the sources of that great river in central Africa. Among the Egyptian special forces is a unit that trains regularly in jungle warfare: there are no jungles in Egypt.
Above all, Egypt worries about Sudan, whose fundamentalist government is increasingly friendly with Iran. Cairo blames extremists across the border for the wave of terrorist attacks that have halved its tourist trade. Egypt may seek an excuse to intervene in Sudan: any 'unauthorised' interference with the flow of the Nile would be an ideal pretext. A more immediate danger to the Nile is posed by Colonel Muammar Gaddafi's 'Great Man-made River' in neighbouring Libya. A huge pipeline carries water from 120 wells, tapping the Kufrah aquifer in the sparsely populated south of the country, to the arid, densely inhabited coast in the north.
According to some hydrologists, the rapid depletion of this aquifer could lead to seepage from the Nile. The Egyptians' worst-case fear is that this action will cause streams from the Nile to flow west into Libya. The Egyptian High Command takes the prospect so seriously that it has drawn up plans to seize an area of south-east Libya until a huge earth-moving operation is carried out to stop exploitation of the aquifer.
The third river system of the Middle East is tiny compared to the others, but the short, muddy Jordan flows through the most hotly disputed territory of all, and is bordered by countries that have shown themselves willing to use force to gain their ends. Nor can the Jordan's flow be improved - so that, if Israel obtains more water, Jordan will receive less, and vice versa.
In theory, peace betweeen the Arabs and Israel should end their rivalry over water, but it is just as likely that water will prevent peace. In a final settlement, Israel would have to give up the West Bank, which gives it control of the southern portion of the Jordan. It seems unlikely to do so, particularly as at least part of its motive in invading and holding southern Lebanon was to have access to the Litani and Hasbani rivers, and the headsprings of the Jordan.
If agreement is reached between Jordan and Israel, but without peace between Israel and Syria, in a decade or so Syria could face an alliance of Jordan and Israel aimed at maximising their share of scarce water resources.
Optimists think that, if a general peace is reached in the Middle East, Arab oil money and Israeli technology may combine to find an economic nuclear or solar way to desalinate sea water. But pessimists outnumber the optimists: King Hussein of Jordan has said he will never go to war with Israel again - except over water; and the United Nations Secretary- General, Boutros Boutros- Ghali, has warned bluntly that the next war in the area will be over water.
Such a conflict seems likely. It is estimated that the Middle East's population of 314 million will rise by 34 million within 30 years, with an annual water requirement of 470 billion cubic metres annually - 132 billion more than the total available, even with a dramatic improvement in conservation.
As it is, per capita water consumption in such comparatively developed Arab countries as Jordan is only about 80 litres a day, while Israel's, at about 300 litres, is on a par with the European average. Oman has already trimmed its development programme to take account of high population growth, and other countries will soon be forced to follow suit.
Engineers and hydrologists all over the Middle East are planning dams and diversions, more desalination plants and improved water use, including elimination of leaks (which waste 15 per cent of all water) and inefficient irrigation (whereby 60 per cent is lost before reaching its target).
All accept, however, that their projects demand the political will to allow cross-border co-operation - and that will still seems to be sadly lacking.
Most chilling, and perhaps most telling, was an off-the- record comment by a leading politician about his country's water needs. 'A time may well come,' he said, 'when we have to calculate whether a small war might be economically more rewarding than putting up with a drop in our supplies.'
John Bulloch is the author, with Adel Darwish, of 'Water Wars: Coming Conflict in the Middle East', to be published by Gollancz on 22 November