To and from far corners of the earth, a semisecret flow of uranium, skilled scientists, and technology helps spread the knowledge needed to build and detonate nuclear weapons.
This newspaper, in a three-month probe, has unearthed new facets of this flow. Involved are Libya, the impoverished Saharan state of Niger, Pakistan, the Soviet Union, India, South Africa, and Israel.
* Libya, led by ambitious, expansionist, terrorist-supporting Col. Muammar Qaddafi, is buying up and stockpiling uranium. He plans to try to sell it in exchange for know-how that could be a shortcut to his dream of owning nuclear weapons.
He has just bought 1,212 tons from Niger, which is outside the framework of international safeguards. That framework requires countries selling uranium to report all sales to the International Atomic Energy Agency in Vienna.
The tonnage figure is in Niger's Gazette Officielle, confirmed and relayed to this newspaper by US diplomats in the capital of Niamey.
This newspaper's research casts doubt on whether Niger reports all its sales.
Israeli intelligence sources, experts in Vienna, and other analysts tell me that Tripoli is selling hundreds of tons of ''yellowcake'' uranium (the first stage of refinement after uranium is dug from the ground) to eager buyers, including Pakistan.
Pakistan is driving hard toward its own nuclear device. It will be able to explode one by the end of next year.
Israeli and Arab sources say Libya provided Pakistan with money and uranium during the 1970s and is now pressing President Zia ul-Haq for nuclear secrets in return. President Zia, whose relations with Colonel Qaddafi are cool, has so far refused. Israel watches with the utmost anxiety.
''What if Pakistan needs money in a few years' time and does decide to sell Libya nuclear secrets?'' one Israeli official asked in an interview in Tel Aviv. ''Who will condemn Libya or Pakistan? Pakistan needs money. Islamic and third-world countries will oppose censure at the United Nations.''
Israel sent F-16 jets over Baghdad June 7 to bomb the Osirak reactor being built for Iraq by France. A major question for the world now is whether the Menachem Begin government in Jerusalem, or another, would bomb other reactors or installations to stop other Arab or Muslim countries from going nuclear.
* Libya had 65 students enrolled in nuclear engineering courses in US universities in the 1980-81 year, according to a computer analysis performed for this newspaper by the Institute of International Education in New York. The percentage of nuclear to ordinary students for Libya was much higher than the same percentage for other countries. The previous year the nuclear figure was 23 - one more than the 22 students Libya sent here to study petroleum engineering.
Details of the computer analysis appear below. They make it clear Libya is trying hard to develop a body of trained nuclear engineers - in a country that is only now receiving its first research reactor (from the Soviet Union). Hundreds more Libyans are studying nuclear technology in Western Europe and in Moscow.
* Libya, the Monitor has learned, is also engaging in some remarkably sophisticated and ambitious physics research - helped by the Soviet Union. The research worries Israel and has raised some scientific eyebrows elsewhere.
Moscow is not only building a research reactor, but also is building in Tripoli a research device aimed at harnessing, through a process called fusion, the basic energy source of the universe and the stars, including the sun.
The device, first developed in the USSR, is called a ''Tokamak.'' It uses magnetic fields to confine low-density plasma. Research in the Soviet Union, the US, and elsewhere is on the way to confining the plasma for one-third of a second. If that can be done, fusion of deuterium and tritium can take place. Enormous amounts of energy would be released. The process may not be commercially usable until early in the next century.
It may sound fanciful for an undeveloped state like Libya to even think of acquiring one. But sources close to British fusion research at Culham in Oxfordshire confirm that the Soviets are, indeed, building a research Tokamak device at the Libyan atomic research facility in Tripoli.
In 1975, it is learned, Britain helped Libya start its fusion research by providing the Alfateh University with a device known as a ''Theta pinch,'' which also confines plasma.
''What worries me,'' said an Israeli official, ''is that a Tokamak can also produce plutonium by bombarding a mantle of natural uranium with neutrons.''
Said an IAEA official in Vienna: ''Yes, but there are much simpler ways of making plutonium.'' A British source agrees: ''I don't see how a small Tokamak helps the Libyans build bombs.''
But Israeli suspicions run deep. They believe Libya tried to buy a bomb from China in 1970 - an episode recounted in the book ''Road to Ramadan'' by Muhammad Heikal, confidant of the late President Nasser of Egypt.
Libya is so confident of its physics program these days that it applied for membership in the prestigious International Union of Pure and Applied Physics (IUPAP). According to IUPAP secretary Larkin Kerwin in a telephone interview from Ottawa, the application was accepted in Paris last summer. Professor Kerwin said he knew nothing of a Libyan Tokamak. But other sources confirmed it.
* Meanwhile, Moscow has been playing its own brand of nuclear politics with uranium.
Late last year the Soviets reportedly sent Libya 11.5 kilograms of highly enriched uranium for the research reactor it is building for Colonel Qaddafi.
''We wish Moscow had not shipped it so far in advance,'' said one US analyst.
''It's another example of how casual this shipment of dangerous nuclear material is becoming,'' another US source said. ''Highly enriched uranium isn't cornflakes, you know.
''It's a holocaust in a box.
''Approached for an explanation by US representatives, Soviet officials shrugged. ''What can Libya do with only 111/2 kilograms?'' they asked. True, the IAEA in Vienna estimates 25 kilograms of uranium is needed for a bomb. But Washington frets, nonetheless.
The Soviets also tried to use their enriched uranium stocks to embarrass the US in India in 1970, the Monitor has learned.
In 1979, the late Premier Alexei Kosygin offered to supply the Tarapur reactor near Bombay with low-enriched uranium, for which New Delhi already had a contract with Washington. The reactors supply electricity for the huge Bombay region in southwest India.
Both Indian and US sources confirmed Mr. Kosygin had made the offer. The Indians refused it, saying they still hoped the US would honor a 1963 contract to supply the fuel for Tarapur (a US-built reactor). Mr. Kosygin made his move with what seemed shrewd timing: In 1978, the US Congress had granted President Jimmy Carter new legislation banning US fuel or technology exports to any country refusing to accept ''full-scope,'' or complete, international inspection of all nuclear facilities. India, while a member of the IAEA, has refused such safeguards.
It has also rejected the 1970 Nonproliferation Treaty, the cornerstone of global safeguards against the diversion of enriched uranium or plutonium for nuclear weapons.
The years 1979 and 1980 were a grace period in which countries had to decide whether to comply with the new US law. India has refused. US fuel has been terminated, despite Indian protestations that the 1978 act violates international law because it cancels existing agreements between states.
* This newspaper has also been told India has decided once again not to accept the Soviet offer, despite the US fuel cutoff.
Instead, Indian sources say, it will fuel Tarapur with a mixture of uranium and plutonium oxide fuel - or MOX as it is known. MOX has never been tried on such a large scale before.
Meanwhile, the US wants to ensure that Tarapur remains under inspection by Vienna. Inspections were required by the US when it started selling fuel originally.
Indian sources say they reject the US legal position, but New Delhi plans to go ''some way'' toward meeting US concerns.
Meanwhile, the latest talks on Tarapur fuel in Washington, held last month, made little progress.
* A little-known fact about the global flow of uranium is that Britain received almost half of its uranium needs in recent years from the controversial strategic area known as Namibia (South-West Africa).
British officials confirmed to this newspaper figures dug out by a United Nations study group. Black African states regularly protest to London. But the British point out that no United Nations resolution bars nonmilitary trade with South Africa, which controls Namibia. The territory is one of the world's largest sources of uranium. Black Africans fume, because Britain is one of the countries that has blocked such resolutions in the Security Council.
The UN estimates that Britain gets 40 to 60 percent of its uranium from Namibia these days.
Uranium dug out of mines around the world is not subject to international safeguards. Countries that are part of the nonproliferation network (i.e., are members of the IAEA in Vienna, or have signed the 1970 Nonproliferation Treaty) are supposed to report uranium sales to Vienna.
Two loopholes: Niger, which has not signed the NPT (as the treaty is known for short), and Namibia, controlled by South Africa, which has likewise stayed away from the NPT.
Niger, however, is supposed to publish sales in its Gazette Officielle in Niamey, its capital.
Niger officials in Vienna had said I could talk about exports only in Niamey, the capital. Israeli sources had told me flatly that Libya was buying large amounts and had just sold 200 to 300 tons to Pakistan.
Some scientists and officials argue that Vienna should spend little time on uranium movements, since safeguards begin these days only when uranium is refined into hexafluoride gas or otherwise refined.
But others disagree.
''If Libya is selling Niger uranium to Pakistan, then Libya is helping Pakistan make fuel rods that produce plutonium that can make weapons,'' one senior US official pointed out.
It is also worth remembering that the original idea for safeguards was to control uranium from the moment it was dug from the ground. The Acheson-Lilienthal report of 1946, which formed the basis of the plan the US presented to the fledgling UN that year, proposed an international body to control all uranium as well as plants.
Joseph Stalin rejected that idea out of hand. He, too, was determined to possess the bomb the US already had. Ultimately, a decade later the Vienna agency was given the right to begin safeguards and inspections only when uranium had been refined.
''No country wants to yield enough sovereignty so that inspectors crawl in and out of its mines, getting in the way and snooping around,'' as one IAEA source says ruefully. ''Anyway, we just don't have the inspectors enough to do it.
''This correspondent asked the Arms Control and Disarmament Agency in Washington for a record of Niger's sales in recent years. The agency said it did not have the information on file.
But it sent a cable to US diplomats in Niamey, asking them to copy out all entries in the Gazette Officielle.
When the reply came in, it revealed that there have apparently been only 12 volumes of the Gazette so far. They began in 1980.
It is not known whether sales made before then, and reported by the Agence France-Presse news agency, were recorded accurately - or, indeed, if even the Gazette Officielle tells the whole story.
Washington officials did some checking and supplied me with dates on which sales mentioned in the Gazette had been approved. The results were interesting, to say the least.
Niger is the fifth-largest producer of uranium in the world. Last Jan. 28 it approved 100 tons of yellowcake uranium for Iraq, a country determined to continue its nuclear ambitions despite the Israeli raid against it last June 7. The next day it approved 125 tons for West Germany.
One thousand tons went to France and another 693.3 tons to France, on March 3 - hardly surprising, since French interests control both major mining consortiums in Niger, SOMAIR and COMINAIR.
France bought another 600 tons four days later, and Spain 300 tons two days after that. Not long after (no exact date is known), 806.6 tons went to Japan. On June 8, Japan bought 10 more tons.
But the most interesting entry of all was another on June 8: a sale to Libya. It totaled 1,212 tons, an enormous amount for a country that has no commercial power reactor whatsoever, and whose highly enriched uranium fuel for a new research reactor comes, under safeguards, from the same country that built the reactor: the Soviet Union.
According to an Agence France-Presse report from Niamey last Aug. 27, Libya bought only 258 tons in 1978, 150 tons in 1979, and 180 tons in 1980. So the latest purchase is a remarkable jump.
One clue comes from an interview given by the President of Niger, Seyni Kountche, cited by United Press International last April.
Noting that uranium prices had fallen 30 percent because of a world oversupply, President Kountche said Niger's share of 1981 mining would be 800 tons. ''It goes without saying that for the development of our country, we cannot store 800 tons of uranium,'' he remarked.
At the same time, Niger was important to Libya politically. The June 8 sale of uranium came just two weeks before the start of the annual meeting of the Organization of African Unity in Nairobi. Libya was scheduled to become chairman for 1982, which meant the 1982 meeting would be held in Tripoli - a splendid forum for Colonel Qaddafi to use.
But behind the scenes, he faced opposition to his chairmanship. Observers who followed events closely said Qaddafi badly needed Niger's swing vote in a crucial committee meeting to head off an open fight and debate. He got it.
The observers speculate Libya's large purchase of Niger uranium may have been designed, in part, to woo President Kountche by disposing of his surplus stocks, perhaps at prices above the depressed world market.
''I also think Qaddafi just wants to pick up influence wherever he can in nuclear matters,'' commented one US official. ''He'll stockpile uranium, sell it to Pakistan, and France, and try to keep his hand in the nuclear game that way. He's constantly on the lookout to buy nuclear technology or even a bomb. . . .''
Colonel Qaddafi's nuclear ambitions are part of the exasperation the Reagan administration feels about him at the moment. Northern Chad, experts note, contains considerable uranium reserves, which Colonel Qaddafi is said to be eying with interest.
Between 1967, when mining began, and 1980, Niger produced 13,000 tons of uranium. According to Uranium Resources, a joint publication of the IAEA and the Organization for Economic Cooperation and Development, Niger's potential could rise to 5,000 tons a year by 1983 and 12,000 tons a year by 1986.
The underdeveloped desert country of 5 million people has little else to sell. The fall in uranium prices has hurt its mines, located near Arlit in the northern desert about 500 miles from the Libyan border.
Niger's ties with Libya were strained earlier this year: In January Niger suspended all sales of uranium to Tripoli after Libya attacked and occupied neighboring Chad.
But Niger needed cash badly, and those sales have clearly resumed.
Not far behind Niger in size or in uranium output is the territory of Namibia , farther south, sparsely populated but strategic, about twice the size of California, still administered by South Africa even though the UN is pressuring for it to be granted independence.
According to figures from the UN and industry sources, Namibia currently produces around 4,000 tons of uranium a year from the huge open-cut mine operated by Rossing Uranium Ltd.
Since South Africa is not a signatory of the Nonproliferation Treaty of 1970, it could in theory sell its own and Namibian uranium to anyone it chose - something black African states suspect. Sources say they believe - but cannot prove - that Namibian or South African uranium has been going to Israel, for instance, or even to be mixed with other shipments to Pakistan.
Black Africa is upset that Britain gets so much of its uranium from Namibia.
Asked about UN reports indicating that about 50 percent of Britain's commercial uranium supplies come from Namibia, a senior official in the British Department of Energy said, ''Yes, something like that.
''And, yes, we are criticized at the UN about it, and at other international meetings as well,'' he added. ''Of course, plenty of other countries trade with South Africa, you know.''
Major industrial states are in too much need of uranium and other strategic metals and other goods to permit a formal UN ban on nonmilitary trade with South Africa.
According to figures cited in a 1981 UN document entitled, ''South Africa's Plan and Capability in the Nuclear Field'' (compiled by a group of Swedish, Soviet, Venezuelan, Nigerian, and French experts for the UN Center for Disarmament), about 65 percent of British requirements until 1982 will come from Namibia. That was said to work out to about 1,300 metric tons a year.
Another UN document, on the exploitation of Namibian uranium (Nov. 20, 1980), gives a different figure: 7,500 tons of uranium between 1976 and 1982, or 42 percent of Britain's needs for that period. Price: $72 million.
A contract with the British was held by Rio Tinto Zinc Corporation Ltd. (RTZ) , which in turn owns 46.5 percent of Rossing, which operates the mine. South Africa also holds a large share. Smaller shares belong to Canadian and French companies.
British officials say when Britain signed its original contract with RTZ, the uranium was coming from Canada. RTZ has since switched to supplies from Namibia to fulfill its contract. The UN report alleged this was because labor costs at Rossing are lower.
The UN document leveled a battery of charges at almost everyone involved, reflecting general unhappiness among black and other UN member states.
It said the British contract was now held by British Nuclear Fuels because of parliamentary opposition to the Atomic Energy Agency's dealing with Namibia.
The document, drawn up for the UN Council on Namibia, said that until late 1979, uranium was flown from Windhoek by South African Airways Boeing 707 jets and French UTA DC-8s.
SAA flew across the ocean via Cape Verde and on to Marseille and Orly in Paris. UTA flew over Angola, Zaire, and Gabon to Marseille and Paris (to the Charles de Gaulle Airport). Onward shipments to Britain went by truck. After some unfavorable publicity, the flights ceased. Ships arenow used, the document alleged.
Moreover, South Africa itself mines and sells uranium. Figures from the IAEA and the Organization for Economic Cooperation and Development show that South Africa produced 5,195 tons and Namibia 3,692 that year - 23 percent of world production for that period.
The South African government has formally stated that it will not allow uranium sales to increase the number of nuclear weapons states. Black African and other critics, however, say it exports so much that the danger of theft and diversion is always present.
Clearly, sales of Namibian (not to mention South African) uranium are lucrative. One UN estimate is that Namibian sales alone, in 1977 prices (which have since risen) were worth about $440 million a year.
It is not known whether Namibian mine production and sales are registered with the International Atomic Energy Agency.
In a long interview at Pelindaba, headquarters of the South African Atomic Energy Board, located between Pretoria and Johannesburg, the president of the board, Dr. J. W. L. de Villiers, would not discuss Namibia.
(On his coffee table, however, lay an illustrated publication entitled ''Rossing,'' the name of the Namibian uranium mine).He did confirm the value of South African uranium exports, saying that production was running at around 5, 000 tons a year. If production rose to 10,000 tons a year, he said, South Africa would have enough uranium reserves to last only about 50 years.
Again, he did not refer to the extremely large reserves in Namibia, which his country controls. Current talks on the independence of Namibia will need to confront Pretoria's desire to keep its access to Rossing output.
As for Libya - it ''gives everyone the cold shivers,'' as one US diplomat puts it.
Israeli sources insisted to me in Vienna that Colonel Qaddafi was using Libya's stockpiled uranium to make sales to Pakistan, among other customers. Israel alleges the IAEA is unaware of such sales, and cites this alleged ignorance as one more reason it cannot put full faith in IAEA safeguards on Iraq or any other country hostile to Israel.
IAEA officials don't usually talk openly about information provided by member states. Libya has signed and ratified the Nonproliferation Treaty, but signed an IAEA safeguards agreement only last summer. In theory it is supposed to inform the agency when it sells uranium. Whether it does so is not known. IAEA officials say they are ''aware'' of Niger sales to Libya.''
Qaddafi is a wild card,'' comments one US official. ''He's fishing around for influence, and for weapons.
The Libyan leader has contracted with the private West German company OTRAG (Orbital Transport-und-Raketen-Aktiengesellschaft) in Munich for a long-range rocket. He says it is designed to put into orbit weather or telecommunications satellites.
US sources estimate the rocket's range at between 1,200 and 1,800 miles. Still in the testing stage, it could be fitted with conventional and, ultimately , nuclear warheads, the sources say. US officials are studying OTRAG, which has been heavily criticized by the Soviets and others.
The company insists that it is not in the business of making ''military rockets.'' The West German government is limited in its powers over a private company that has broken no law. US officials are in no mood these days to take a kindly view of Libyan intentions. They are concerned that Qaddafi wants the rocket as a way of gaining diplomatic leverage.
Libya has a surprising number of its students studying in the United States to be nuclear engineers. While the absolute numbers are small, computer analysis yields some reavealing percentages.
Libya had 2,290 students in the US in 1978-79. The figure leaped by one-third to 3,030 the following year and rose to 3,080 in 1980-81.
The computer analysis looked at percentages of Libya's nuclear engineering students to all its students on file. It came up with 2.4 percent. That was higher than the similar percentage for all countries combined - 0.3 percent.
The computer discovered that Libya's 23 nuclear engineers in 1979-80 accounted for 5.7 percent of all nuclear engineering students from abroad, even though Libya accounted for a mere 1 percent of foreign students.
By contrast, Pakistan had only three nuclear engineering students in the US in 1979-80. Iraq had only six. The figures in 1980-81 went up to four and eight, respectively.
So the analysis shows that Libya has a significantly higher percentage of its students in the US studying nuclear know-how than do other developing countries.
Added to that must be the Libyans studying nuclear engineering in Western Europe and the Soviet Union.
In 1979-80, 16 Libyan nuclear engineers were in US undergraduate schools, seven in graduate schools (five masters, one doctorate, and one unspecified).
An article in the Bulletin of Atomic Scientists (August-September 1981) estimated 200 Libyans studying nuclear engineering in the US. It put the number in Europe at 200-300, and more in the Soviet Union, ''many times the number that could be realistically absorbed by a civilian nuclear program.''
At least one American expert is convinced that Libya is trying to buy a bomb. He says the Libyans told him so in 1978.
Jeremy Stone is director of the Federation of American Scientists (FAS) in Washington.
In an interview with this newspaper he described his visit to Libya in 1978 and added details to an article he wrote on his return:
''I talked around a table with several senior Libyan officials, including Ahmad Shahati, who was head of the foreign liaison office of the People's General Congress.
''Their government uses different names than ours, but it's an important post. Shahati told me outright Libya wanted a bomb for its own defense. I pressed the point to be quite sure, and asked if he wanted the right to get a bomb, or a bomb itself.
''He was quite clear: Libya wanted a bomb.
''Well, I returned to the US and said I thought Libya, which had signed the Nonproliferation Treaty, was a false adherent of that treaty.
''Then the Libyans denied they'd told me any such thing. But I know what I heard.''You know Muhammad Heikal's 1975 book, 'Road to Ramadan.' '' (Heykal is the journalist who was a close friend of Nasser.)
''He tells how Qaddafi sent his deputy, Major Jalloud, to Nasser in 1970 to ask if the Israelis had the bomb. When Nasser said he thought they did, Jalloud went off to Peking to try and buy one. The Chinese refused.''
In the Bulletin of Atomic Scientists, August-September 1981, a Vancouver professor, Joseph Micallef, says Libya has looked to Argentina for technical aid. The Soviet Union is building a small power reactor, has promised both a 440 -megawatt reactor under safeguards, and a 300-megawatt reactor to operate desalination plants and pump underground water.
With recycling, the article says, the desalination plant would yield enough fissionable material for 10 to 20 bombs per year - though such a prospect is still a long way off.
Also part of the uranium story are persistent reports that Israel obtained, by secret means, 200 pounds of enriched uranium from a nuclear processing plant in Apollo, Pa., in the mid-1960s - and 200 tons of natural uranium in cans marked ''Plumbat,'' from a West German merchant ship that vanished for several weeks in 1968 en route from Antwerp, Belgium, to Genoa, Italy. When the ship reappeared, it had a new name, a new crew - and no uranium.
Former CIA senior official Carl Duckett said earlier this year on ABC-TV that the CIA had long since concluded Israel had probably fabricated nuclear weapons using the Pennsylvania uranium.
Paul Leventhal of the Nuclear Club Inc., who first released news of Plumbat, indicated to me his belief that the uranium was certainly stolen, but he would not say by whom.