Shortly after midnight on November 8, 2007, four armed men broke into the Pelindaba nuclear facility just west of Pretoria, South Africa, with its contents of hundreds of kilograms of highly enriched uranium, the critical ingredient for a nuclear bomb.
Two of the gang managed to get through a 10,000-volt security fence, disable the alarms and shoot an employee in the emergency control centre. Closed circuit television cameras caught their images, but no one was monitoring them. By the time the wounded man raised the alarm, the gang had spent about 45 minutes inside the facility, which holds enough nuclear material for 25 bombs, without attracting a shade of suspicion.
Finally, with police sirens wailing in the distance, they escaped empty-handed the same way they entered. Although three men were later arrested in connection with the incident, no one was ever convicted. It was one of the worst known security breaches at a nuclear site. If the gang had stolen a fraction of the enriched uranium for themselves or to sell on the black market to a terrorist group such as al Qa'eda, which has been seeking a nuclear weapon for 15 years, the consequences would have been devastating.
Just 60 kilograms of enriched uranium, enough to fit into two 2-litre bottles, is enough to create a crude nuclear bomb that, if set off in the centre of a major city such as New York, Paris or Cairo, could kill hundreds of thousands of people and cause hundreds of billions of dollars' worth of damage. There are 1.6 million kilograms of weapons-grade uranium stored in hundreds of buildings all over the world, a deadly and forgotten hangover of the Cold War. In some places in Russia they are protected behind little more than a chain-link fence.
It was the prospect of this material falling into the hands of terrorists that sufficiently alarmed the US president Barack Obama to last week host the largest gathering of world leaders on US soil in 65 years in order to get them to promise they would protect their nuclear chemicals and sites. After the two-day summit in Washington, 47 countries, including the UAE, pledged to lock up or destroy by 2013 any highly enriched uranium and plutonium they may have.
"It is a race between catastrophe and co-operation," said Matthew Bunn, a leading expert on nuclear terrorism and associate professor at Harvard University's Belfer Center for Science and International Affairs. Security on the stocks needs to be urgently improved to prevent them being stolen, he warned. But critics pointed out that the joint action plan was not legally binding and there had been no agreement to stop producing enriched uranium or plutonium.
Many developing countries do not see pouring money into protecting nuclear sites as a national priority because they think only America and Europe are targets for nuclear terrorism, according to Ian Kearns, a senior analyst at the British American Security Information Council, a research and advocacy organisation. "One has to be very clear about what is at stake with the nuclear agenda," he said, in an interview from London.
"If there was an incident of nuclear terrorism, what happens thereafter? You can imagine if al Qa'eda attacked. You can see them saying, 'Actually we've got more. We will blast more at a time that we choose.' Even if it was not true there would be panicked emptying of cities globally. If an incident happened in an American city, the US would be under enormous pressure to use enormous military force to target whoever is connected in any way. You'd have widespread instability and conflict."
Chile, whose nuclear research programme produces enriched uranium, recently sent its entire stock of highly enriched uranium to America, as a security measure. The difficulty of keeping such material safe was highlighted by the fact that some of the evacuation took place during the devastating earthquake on February 27 in which hundreds of people died. Nuclear weapons are heavily guarded all over the world and many now have hi-tech security features, so that if the wrong code is inserted too many times the weapon is permanently disabled.
As a result al Qa'eda, which has called obtaining a nuclear bomb a "religious duty", appears to have shifted its focus from stealing a ready-made weapon to building a crude version with materials bought on the black market. There are 18 known cases of weapons-grade material being stolen over the past two decades. In cases where materials was seized by authorities, no one knew they were missing in the first place, calling into question how much is floating around on the international black market.
Plutonium is hard to detect by airport X-ray machines. There is also uncertainty over whether weapons and materials left behind when the Soviet Union collapsed have been fully accounted for. In Georgia, authorities have foiled eight attempts at trafficking enriched uranium during the past 10 years, most recently last month. "Criminals associated with these attempts have been detained," the Georgian president told the Washington summit.
A relatively simple bomb involves slamming two pieces of highly enriched uranium together at a high speed and can be assembled with the right expertise and smuggled in the back of a van. Al Qa'eda, whose fighters include many from the scientific and technical professions, appears to be trying to build a bomb. In 2003, US intelligence agents were alerted to an al Qa'eda cell in Saudi Arabia that was negotiating to buy three nuclear devices from a Pakistani expert, said Mr Bunn.
"Probably they weren't real nuclear weapons but that's what they thought they were and they got a message from al Qa'eda central saying 'go ahead and make the purchase if the Pakistani expert confirms they are real'. We've never managed to identify who that Pakistani expert was." The biggest cause for worry apparently is Pakistan, which has between 60 and 90 nuclear weapons stored at several sites, plus several plutonium and highly enriched uranium reactors under construction.
"The risk of a WMD attack being planned and executed from Pakistan's North West Frontier area is growing, as that area continues to function as a safe haven for al Qa'eda," stated a 2008 report by a US congressional commission. The US has given Pakistan US$100 million (Dh367m) in technical assistance to secure its nuclear facilities, but the Americans have never been given access to any of them, partly because of high anti-American sentiment.
An elite military unit of several thousand soldiers protects the sites, but there are fears that the upper echelons of the military and political establishment have been penetrated with radical sympathisers. "The problem is not that Pakistan doesn't have good security for its nuclear stocks. It does. The problem is the huge scale of both insider and outside threats," said Mr Bunn, pointing out that the former president Pervez Musharraf has had two close calls with assassinations.
"If the military personnel guarding the president cannot be trusted, how much confidence can the world have in the military personnel guarding the nuclear weapons?" That is where America did not get it right at the Washington summit, said Mr Kearns. "They need to universalise the effort and have a UN framework or convention. There is a conversation among diplomats about having a UN convention which would allow countries such as Pakistan to ask for assistance in a global framework and not just look like they are asking the US for assistance. That would be politically much easier for the regime."
Mr Bunn said that preventing insiders from selling or stealing nuclear materials was the first line of defence. "Once it has left the door of the facility where it is supposed to be, all of the later lines of defence are later variations of looking for needles in haystacks. The place where you really know you can do something is at the site where you know the nuclear material is supposed to be, locking it down there and making sure it doesn't walk out the door in the first place."