The nuclear disarmament race developing between the US and Russia is generating vast new global risks of nuclear terror.
But there is debate about just how far the world can afford to go in policing the black market sales of nuclear materials - from the seemingly less innocent medicinal and industrial radioactive materials to full-fledged weapons-grade materials.
A stormy debate is expected at October's meeting of the International Atomic Energy Agency (IAEA) in Vienna over Euoropean pressure to establish different standards - depending on the grade of plutonium - for anti-smuggling enforcement. Germany and France argue that it would save time and bureaucratic trouble.
But the US vehemently opposes the idea, arguing that plutonium generated in commercial reactors and containing less fissile material than weapons-grade plutonium can still be used for building a bomb and should be treated with utmost caution.
Most of the 130 cases of smuggling tracked by the IAEA in the past five years concerned the attempted sale of nuclear materials used in medicine or industry.
Other cases involved weapons-grade material, raising fears that terrorists or rogue states might be aiming to get ahold of some of the disintegrating nucelar arsenal of the former Soviet Union.
Diplomats at the conference will be haggling over provisions of the Convention on Nuclear Safety - the first international legal instrument on the security of atomic reactors and their products - which recently entered into force. The Convention involves the framework for general safety factors, radiation protection, emergency preparedness, and a long list of specific obligations to reduce risks.
"The convention marks a major step forward in strenghtening international cooperation in the safety field.... [It] signals the growing recognition of global interdependence in safe nuclear development," says Dr. Hans Blix, the IAEA director general.
He describes a nuclear disarmament race between the US and Russia, generating enormous new risks.
"Weapons are being dismantled at such a pace," he explains, "that the management and storage of freed plutonium and highly enriched uranium are now posing problems. This agency must help to prevent any re-use of such materials for weapon purposes."
The disarmament race is being fought with all the passion that once fueled the arms race. The Atomic Engery Ministry in Moscow has just acquired two US-made super computers of the sort that the White House has forbidden US manufacturers to sell to Russia. Moscow says that the machines have been purchased legally from third parties for $7 million. They will be deployed to oversee the security of nuclear materials.
The risk factor is beyond measure, observes a new study from the Center for Strategic and International Studies, a Washington think-tank.
"We are worried because Russia has become a criminal state," explains Sarah Mullen of the Arms Control and Disarmament Agency of the US State Department, and was involved in the committee that prepared the report.
Morale within the Russian military is phenomenally low, she says, and the corruptibility of officials is high. Her committee fears that the surge of organized crime in Russia is increasing the danger that nuclear materials, possibly even complete warheads, might end up in the hands of terrorists or states determined to acquire them.
International collaboration to smash the trade in fissile material moved into top gear following a nuclear security summit conference in Moscow last year.
Among IAEA's intelligence and security programs are safeguards including enhanced evnironmental monitoring and direct inspection of nuclear installations. These are undertaken by the agency to prevent rogue states from engaging in concealed nuclear weapons programs, as Iraq did before the Gulf war. But some countries including France and Germany regard such measures as too costly and intrusive.
The IAEA proposes to compromise by establishing different categories of safeguard procedures for the different grades of plutonium involved.
This would make sense if reactor-grade plutonium containing less of the fissile isotopes than weapons-grade plutonium were also less dangerous. But the proposal is likely to provoke controversy because documents declassified by the US this year reveal that both grades of plutonium would be suitable to power a crude nuclear device with more than half the destructive capacity of the 1945 Hiroshima bomb.
* Thomas Orszag-Land writes from London on global affairs.