by Alok Jha
In the 1980s, Ronald Reagan started talking publicly about his Strategic Defense Initiative (later nicknamed Star Wars), a system of lasers and explosives that would protect the US from nuclear attack. After the relative calm of the 1970s, the fact that the American president seemed unafraid of such an attack was a surprise to the Russians. The new US administration stepped up the rhetoric, playing up the country’s strengths and playing down the more apocalyptic scenarios of a post-nuclear fallout.
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Right now we have a system in place which would automatically launch all missiles remaining in our arsenal, even if every nuclear command center and all of our leaders were destroyed.
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Reagan maintained that Star Wars was purely defensive, but officials in Moscow suspected that in reality the Americans were preparing an attack. The Soviets were not keen to jump the gun and attack pre-emptively, so Perimeter became a way for them to be sure that theirs would not be the only country destroyed if the US launched their arsenal. If nothing else, it was a good deterrent.
But as any military analyst knows, a deterrent is only effective if your enemy knows what you will do in the event of an attack. Unfortunately, there is no evidence that any senior US officials knew anything about Perimeter. This made it a strategy in which even the mad scientist in Kubrick’s film would have noticed gaping holes.
When Dr. Strangelove, played by Peter Sellers, is told about the 50 secret nuclear bombs covered in cobalt waiting to explode automatically if the USSR is attacked, he exclaims: “Yes, but the ... whole point of the doomsday machine is lost if you keep it a secret! Why didn’t you tell the world, eh?”
Could it be used today?
Perhaps the most alarming thing about Perimeter is that it seems to be plugged in to this day. “We don’t really know if there’s still a switch in the Kremlin,” said Hoffman in an interview with Terry Gross on National Public Radio in the US. “But that aside, I think the command rockets, the bunker, the entire Perimeter system is still there and waiting. And I think the command system part of it is still functioning ... I’ve been told that that command structure may have changed. But I do know that the men in the bunker are still there. The system is still alive. It’s still a command system.”
Whether Perimeter, or any other secret system like it elsewhere in the world, could be switched on in the future depends on the diplomatic relations between the ever-growing number of nuclear powers. Nuclear weapons might have seemed the best way to keep the world away from war in the past. But disarmament has never looked like such a good idea as it does today.
Mutually Assured Destruction
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Global nuclear war is supposed to be a thing of the past, a relic of the Cold War. But human desperation for power never ends and, with the emergence of new nuclear states, the threat of annihilation is ever present.
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Wars are usually about each side weighing up the risks of fighting in the hope that, if they succeed, something better lies on the other side. A sacrifice is made for the good of a greater goal.
Not so with mutually assured destruction, however, a term devised during the Cold War to describe what would happen if the two superpowers, the US and the USSR, did what they were always threatening to do and launched their thousands of nuclear warheads at each other. Both sides knew that the act would be catastrophic not just for themselves, but for the planet too. The phrase says it all: if two sides go to war, both can be assured of the complete destruction of the other.
In a nuclear strike, millions of people would die in the initial blasts and firestorms where the bombs detonated. Further afield, billions more would perish from sickness and starvation in the months and years that followed, a consequence of the Earth’s sudden transformation into a barren wasteland where no plant or animal could survive.
And if you thought it was something consigned to history, think again. Scientists, armed with powerful computers and sophisticated weather models, have shown that even a regional conflict (between, say, India and Pakistan) could release enough smoke into the atmosphere to devastate global agriculture for many years and lead to widespread loss of life outside those two countries. The acronym for this type of nuclear war, MAD, is apt for something with such civilization-ending potential.
The nuclear age
The first nuclear bomb exploded into public consciousness on the morning of 6 August 1945 over the Japanese city of Hiroshima. That bomb, Little Boy, was followed a few days later by Fat Man, the device dropped on Nagasaki. Both killed tens of thousands in their first few moments and cursed countless thousands more with a lifetime of radiation sickness.
The nuclear warheads were developed in the 1940s as part of the top secret Manhattan Project at the Los Alamos National Laboratory. Scientists working for the US military had pipped rival teams working in Germany and, some argue, brought the end of the Second World War closer.
Once the principle of this devastating bomb had been demonstrated, however, it was only a matter of time before scientists around the world would want to come up with their own versions. Fortunately, however simple the concept of a nuclear bomb is, actually building one is no easy feat.
The raw material for a nuclear bomb consists of atoms that will split when nudged. Uranium, a heavy metal that comes in two isotopes called uranium-238 and uranium-235, is ideal. Both isotopes are radioactive and have nuclei that split apart, though only U-235 will split on command, whenever it is bombarded with neutrons. When a nucleus splits, it releases some energy and also more neutrons, which can then go on to split further nuclei. If enough atoms split in one place, the chain reaction becomes self-sustaining.
The problem faced by nuclear bomb engineers is getting hold of enough U-235: you need at least 50 kg to make a bomb. Naturally occurring uranium is mostly U-238, so it needs to be weeded out and the U-235 concentrated into the sample you are collecting. This is where it starts to get difficult: for every 25,000 tons of uranium ore, only 50 tons of metal are produced, and less than one percent of that is uranium-235. And no standard extraction method will separate the two isotopes, because they are chemically identical. Instead, the uranium is reacted with fluorine, heated until it becomes a gas and then decanted through several thousand fine porous barriers. This separates it into two types: “enriched,” which contains mostly U-235, and “depleted,” which contains mostly U-238.
The arms race
After the end of the Second World War, the US and USSR raced to build warheads. The first Soviet bomb was detonated in 1949, much earlier than the US had expected. The 1950s saw the introduction of intercontinental ballistic missiles (ICBMs), which could carry warheads thousands of miles further than strategic bomber planes.
By the 1960s, both superpowers had demonstrated space rockets, ostensibly the start of the race to get satellites and people into orbit for exploration but with the ulterior motive of showing that they could now send warheads wherever they wished in the world.
By 1982, the US had built 11,000 nuclear warheads and the USSR had built 8,000. Both could deliver the bombs via ICBMs and from submarines, which acted as a backup in case command centers were destroyed in an initial attack.
By 1982, the US had built 11,000 nuclear warheads and the USSR had built 8,000. Both could deliver the bombs via ICBMs and from submarines, which acted as a backup in case command centers were destroyed in an initial attack. Both had extensive radar set-ups to track anything anomalous coming their way. And both had been aware for several decades that if they unleashed devastation, the other side would have time to strike back with equal force.
Nagasaki, Japan, was in ruins in August 1945, after a nuclear bomb was dropped on to the city.
Nuclear winter
As demonstrated at Hiroshima and Nagasaki, nuclear bombs will kill anyone and anything within several miles of their detonation. The impact to the wider world comes later, as part of the so-called nuclear winter. In the late 1980s, scientists showed tha
t the smoke from vast fires created during a nuclear war between the US and the USSR would cloud the entire planet and absorb so much of the incoming sunlight that the Earth’s surface would become cold, dark and dry. Plants would die and food supplies would soon be exhausted. Summer would be as cold as an average winter.
More advanced projections of a nuclear winter, using modern climate models and supercomputers, confirmed the sketchy ideas of the 1980s and added detail. The effects would last a decade or more, much longer than previously thought, and the smoke from even a relatively small nuclear war would be heated and driven high into the upper atmosphere for years.
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The Earth’s surface would become cold, dark and dry. Plants would die and food supplies would soon be exhausted.
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Speaking at a meeting of the American Geophysical Union in San Francisco in 2006, Richard Turco of the University of California, Los Angeles, said that detonating between 50 and 100 bombs—just 0.03 percent of the world’s current arsenal—would throw enough soot into the atmosphere to create climatic anomalies unprecedented in human history. Tens of millions of people would die, global temperatures would crash, and most of the world would be unable to grow crops for more than five years. In addition, the ozone layer, which protects the surface of the Earth from harmful ultraviolet radiation, would be depleted by 40 percent over many inhabited areas and up to 70 percent at the poles.
Turco examined an exchange between two countries of 100 Hiroshima-sized nuclear bombs (15 kilotonnes each), a conflict he argued was well within the ability of many emerging nuclear states. The results showed that the most densely packed countries would fare worst in the aftermath of a nuclear war. Because of the recent propensity of the population to move into high-density cities, India and Pakistan could face 12 million and 9 million immediate deaths respectively, while an attack on the UK would cause almost 3 million immediate deaths.
In the 100-warhead scenario, more than 5 million tons of sooty black smoke would spew from the resulting firestorms. This would float to the upper atmosphere, become heated by the Sun and end up being carried around the world. The particles would absorb sunlight, preventing it from reaching the surface, which would result in a rapid cooling of the Earth by an average of 1.25°C. “This would be colder than the little ice age, the largest climate change in human history,” said Alan Robock, a climatologist at Rutgers University who worked with Turco on the analysis.
There would also be a reduction in precipitation around the world, by about a tenth. Blocking sunlight reduces evaporation and weakens the water cycle. In the Asian monsoon regions, rainfall would drop by up to 40 percent.
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100-WARHEAD SCENARIO
India: 12 million dead
Pakistan: 9 million dead
UK: 3 million dead
5 million tons of soot in air 1.25°C global temperature drop
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The model also showed that the smoke would stay in the upper atmosphere far longer than anyone had previously thought. Older models had assumed that it would linger for around a year, as has been observed with the dust from volcanic eruptions. However, using improved atmospheric data, the new study showed that the climate would still be suffering a decade on from the initial conflict.
Is it likely?
During the Cold War, both superpowers were obsessed with being seen as powerful, but neither wanted to be the one to trigger the end of the world. The US and Soviet political leaders had a dedicated phone line in case of emergencies, and they maintained diplomatic relations. When there were just two sides, it was easier for one to keep the other in check.
Today, the nuclear picture is more complex. Nine nations—Russia, the US, France, China, the UK, Israel, Pakistan, India and North Korea—have more than 25,000 nuclear warheads between them. Many more nations might be on the verge of developing the weapons.
Prime ministers and presidents around the world profess to aspire to a dream world in which the number of these weapons is reduced (perhaps to zero).
In July 2009, US president Barack Obama and Russian president Dmitry Medvedev agreed to drop their deployed nuclear arsenal to between 1,500 and 1,675 by 2016. Robock calculated what might happen if this “mother load” of weapons were detonated against urban targets in the US and Russia. Hundreds of millions of people would be killed, and a whopping 180 million tons of soot would be thrown into the atmosphere. Average temperatures would remain below freezing for many years in major agricultural regions.
There is little that will prevent any country determined to produce nuclear weapons from doing so. And there is no sign that countries want to be told what to do by superpower nations that already hold thousands of nuclear warheads.
Writing in Scientific American in 2010, Robock and Owen Brian Toon, chair of the department of atmospheric and oceanic sciences at the University of Colorado in Boulder, said that it was a “misimpression” to think that the nightmare of a nuclear winter had gone away at the end of the nuclear arms race. “In fact, a nuclear winter could readily be produced by the American and Russian nuclear arsenals that are slated to remain in 2012. Furthermore, the increasing number of nuclear states raises the chances of a war starting deliberately or by accident.”
They continued: “Some extremist leaders in India advocated attacking Pakistan with nuclear weapons following recent terrorist attacks on India. Because India could rapidly overrun Pakistan with conventional forces, it would be conceivable for Pakistan to attack India with nuclear weapons if it thought that India was about to go on the offensive. Iran has threatened to destroy Israel, already a nuclear power, which in turn has vowed never to allow Iran to become a nuclear state. Each of these examples represents countries that imagine their existence to be threatened completely and with little warning. These points of conflict have the potential to erupt suddenly.”
Terrorism
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There’s been an explosion in the center of the city. A dozen people are confirmed killed and scores of buildings around the blast site are damaged. Police have cordoned off the immediate area but have also evacuated a five-mile radius. Confusion reigns.
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You turn on the news to see a grave presenter relaying a message from the city authorities: stay indoors, however far you are from the center of the blast. When your partner gets home from work an hour later, she’s heard rumors that the blast contained “something nuclear.”
Later that evening, police confirm that the city has been attacked by terrorists, and the blast was the result of a dirty bomb. Powered by conventional explosives, the device has dispersed a cloud of tiny particles of radioactive caesium into the air. This toxic dust has been settling all over the city for the past few hours, spread by strong air currents.
The police spokesman says that rooftops, roads, pavements and cars within several miles of the initial blast are now likely to be covered with caesium. Airconditioning units will have drawn some of the cancer-causing dust into buildings. He repeats the advice of the authorities, this time with even more urgency: seal your homes and stay indoors until further notice.
In the days after the blast, you are asked to leave home while clean-up crews begin the task of making the city safe for human habitation. What are the chances, though, that you or your neighbors will come back soon, or indeed ever? The bomb might not have disrupted much of the local infrastructure, but the city itself has been wrecked, possibly for good.
Three types of attack
Terrorists will attack law-abiding populations with every means at their disposal—knives, guns or explosives—to get attention for themselves and their cause. Their intent is to strike fear and keep it running high for as long as possible. To get what they want, they need citizens to believe that an attack is imminent at any time. And they have to do it without the resources or funds normally available to governments fighting military conflicts.
In such circumstances, a dirty bomb is disproportion
ately deadly. These are weapons whose dangerous repercussions continue long beyond any initial blast, sowing fear and uncertainty for weeks, months, possibly years afterward.
A typical device falls into one of three broad categories: radiological, biological or chemical.
The radiological dirty bomb (described in the scenario above) is usually made of conventional explosives, such as TNT or a mix of fertilizer and fuel oil, laced with highly radioactive materials. The explosion generates heat that vaporizes the toxic payload, which is then sprayed out over a large area. “Weapons experts consider radiological bombs a messy but potentially effective technology that could cause tremendous psychological damage, exploiting the public’s fears of invisible radiation,” wrote Michael A. Levi and Henry C. Kelly, physicists at the Federation of American Scientists in Washington DC, in an analysis of the threat of bioterrorism for Scientific American in 2002. “Not weapons of mass destruction but weapons of mass disruption, these devices could wreak economic havoc by making target areas off-limits for an extended period.”
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A dirty bomb is disproportionately deadly. These are weapons whose dangerous repercussions continue long beyond any initial blast, sowing fear and uncertainty for weeks, months, possibly years afterward.
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Radioactive dust, such as plutonium or americium particles, can become embedded in people’s lungs, emitting harmful alpha radiation (the energetic nuclei of helium atoms) for years after the initial exposure.
