Overkill (31 page)

The apartment, once so comfortable and secure – a meeting place where the two men could lie together in a familiar embrace – was feeling more and more to Arkenko like a prison. A
comfortable prison, but a prison nevertheless.

With a sigh, he reached for his notepad and began to prepare the radio message.

Cambridge

The professor was well established into his lecture. ‘Matter, of course, can neither be created nor destroyed. What can happen is that matter can be converted into
other sorts of matter, or into energy, as matter and energy can be considered to be different forms of the same thing. This conversion is what happens when you burn coal on a fire, for example. The
energy released when the coal is burnt is the energy stored in the various sorts of chemical bonds holding together the molecules which constitute coal. That’s a simplification, of course,
but it’s accurate enough for the purposes of this discussion.

‘As well as the release of energy, the products of the combustion process are radically different from the original components of the coal or whatever the fuel is. Carbon compounds will
burn to produce carbon monoxide and dioxide, nitrogen compounds to give various nitrous and nitrogen gases, and so on. But the point is that if you have carbon in the original material, you will
have exactly the same amount of carbon in the combustion products. OK?’

Richter nodded, and wondered how long it would be before he started dozing off. ‘Now, in a nuclear reaction, that statement is no longer true. The elements which are present on the left
side of the equation are not the same as those on the right. Matter is actually changed from one element to another, just as the old alchemists were trying to do in their search for the
Philosopher’s Stone centuries ago. Our sun is a vast nuclear furnace, meshing atoms of hydrogen together to create helium. The same thing happens in the detonation of a nuclear weapon. One
element is turned into another, with the release of enormous amounts of energy. And it’s the energy release which marks the practical difference between conventional explosives and nuclear
weapons. A suitcase of dynamite could flatten a building. A suitcase of uranium would flatten a city.

‘This fundamental difference between the two types of explosion is because in a conventional explosive, the energy released is that which binds molecules together, whereas in a nuclear
blast it’s the forces which hold the very atoms themselves together which are ruptured. The stronger the bond which is broken, the greater the energy released, and the atomic bonds are very,
very strong.’ Hillsworth got up and walked over to the wipe board. ‘The actual value of the energy released is given by the mass-energy equation, with which I’ve no doubt
you’re familiar.’ He wrote ‘E = mc
²
’ on the wipe board with a red magic marker, and looked at Richter, who nodded and tried to look intelligent.

‘“E” is the energy released; “m” is the mass of the material used, and “c” is the numerical value of the speed of light, which is then squared.
There’s no need to bother about the units involved; suffice it to say that the value of “c” squared is very high, which is why “E” is so vast.’

Hillsworth resumed his seat. ‘Now, to build a nuclear weapon, you must first of all find some suitable material. It must be fissionable, which means it must be able to be readily converted
into other elements, with the consequent release of energy, which in practice means that it must be one of the very heavy radioactive materials, like uranium or plutonium. Radioactive materials, as
the name suggests, emit sub-atomic particles and certain types of radiation and some, like the isotope uranium 235, have what is called a critical mass. To put that in simple terms, if you simply
assemble more than a certain amount of uranium 235 in one place, it will go critical and a nuclear explosion will result. That, in a nutshell, is the theory of the atomic bomb. Simply find yourself
enough uranium, smash it all together at the desired time and place, and wait for the bang.

‘The mechanics, of course, are much more complicated, which is probably just as well. The normal detonation methods utilize shaped charges, amongst other things, which enable a bomb to be
produced using substantially less fissionable material than in the early days. The bombs I’ve mentioned so far are fission bombs, where a heavy element is broken down into two or more lighter
elements. The hydrogen bomb, on the other hand, combines hydrogen atoms to produce heavier elements, in exactly the same way as the sun functions. Do you want me to go into that as well?’

‘Thank you, Professor. I would appreciate it.’ Richter had learnt nothing new, and nor did he expect to at that stage of the discussion, but one of the first rules of friendly
interrogation – that is, interrogation of a non-hostile subject – is to ask so many questions that it is difficult for the person being questioned to discern what you are really trying
to find out. As far as Richter was concerned, the more Hillsworth said the better, and he seemed to be settling nicely into his lecture routine.

‘Right,’ Hillsworth said. ‘A hydrogen bomb uses a fission trigger wrapped in hydrogenized material to initiate a fusion reaction.’ He paused as the sound of muffled
ringing became audible.

Richter muttered an apology and retrieved his cellular phone from his jacket pocket. ‘Richter,’ he said.

‘This is the Delivery Section,’ the voice at Hammersmith said. ‘We’ve just received a category-four delivery for our main customer.’

On an open line – even for a call routed to a GSM digital cell phone, which was effectively scrambled by the transmitting cell – the proprieties had to be observed. ‘Main
customer’ was America, and a ‘category-four delivery’ was code for DEFCON – DEFence CONdition – FOUR.

There are five stages in the DEFCON process. The normal peacetime state is DEFCON FIVE; DEFCON ONE means that the American armed forces are in a state of maximum preparedness for combat, or are
actually at war. DEFCON FOUR kicks the American military machine into a significantly higher state of readiness, and is the inevitable precursor to any outbreak of hostilities.

‘Oh, shit,’ Richter replied. ‘When?’

‘About twenty minutes ago.’

‘What action?’

‘Back here as soon as you’ve finished where you are.’

Richter snapped the phone closed as Hillsworth got up and made another drink, then he cut to the chase. ‘We have heard, Professor, that the Americans are starting to experiment with a new
device which will produce about the same yield as a conventional nuclear weapon, about five megatons, but emit little or no radiation. I can’t reveal the source of this information, and we
have at present no idea of the way in which such a weapon could function.’

Richter couldn’t tell him the source of the information principally because no such information had been received. Hillsworth sipped his tea slowly, looking keenly at Richter over the rim
of his mug, then smiled. ‘I thought the Americans were on our side?’

‘They are, Professor,’ Richter replied, ‘and that’s why we’re interested. You always know what an enemy will try to do. It’s much more difficult to tell what
your friends are intending, which is why we always look very carefully at any rumours we hear.’

Hillsworth nodded. ‘Very wise, no doubt.’ He looked thoughtful. ‘It’s an interesting idea, but unfortunately impossible.’

‘Impossible?’ Richter queried.

‘Yes. The physics won’t let it work. Whenever a nuclear explosion takes place, radiation products are emitted, and there’s nothing anyone can do to stop that happening. The
radiation is as much a part of the equation as the uranium or plutonium.’

Hillsworth paused and scratched the back of his neck. ‘As we’ve briefly discussed,’ he continued, ‘there are three principal types of nuclear weapon: the fission bomb,
the fusion bomb and the neutron bomb, which is also a fusion device. All emit radiation of various sorts, including gamma rays, x-rays, alpha particles and neutrons. In fact, the neutron bomb is
specifically designed to emit huge quantities of high-speed neutrons which are lethal to all living things, but it’s only a tactical weapon, with no strategic potential.’

‘Why is that?’ Richter asked.

‘Because in a conventional nuclear weapon the neutrons released when the weapon detonates are absorbed to increase the energy of the explosion, to increase its yield. In a neutron bomb,
the neutrons are allowed to escape, which severely limits the maximum possible size of the weapon.’

‘How high a yield could a neutron bomb have?’

‘The theoretical limit is about nine megatons, but most neutron devices were designed to be fired from large-calibre artillery pieces or mounted on small battlefield-use missiles, so
it’s usually down in the few kilotons range. As I said, it’s strictly tactical in its application.’

‘And what about the radiation?’

‘It’s known as an Enhanced Radiation Weapon or ERW, and was always intended to be used to defend the West against a numerically superior attacking force. The neutrons would kill the
attacking troops, but the low yield of the bomb means that it would cause little structural damage, which could be important if you were fighting on your home territory. And the radiation
dissipates quickly, which could also be an advantage.’

Richter was, he thought, perhaps not actually able to see the light at the end of the tunnel, but he was at least beginning to make out the tunnel walls fairly clearly.

Anton Kirov

‘Not another change of plan?’ Valeri Bondarev asked, somewhat peevishly.

Colonel Zavorin nodded. ‘I don’t like it any more than you do, Valeri,’ he said. ‘I am running to a schedule, but it is dictated by Moscow.’

‘So,’ Bondarev said. ‘Now we do not go to Tunis either.’

‘No. We have been told to head straight for Gibraltar, and to signal Moscow with our estimate as soon as possible. My signalman has already cancelled our berth at Tunis.’

‘Thank you very much,’ Bondarev replied, with patent insincerity.

Cambridge

‘So what’s happened to the neutron bomb?’ Richter asked.

‘Well,’ Hillsworth said, ‘it’s always been very controversial, because it’s a people-killer. It was specifically designed to decimate enemy troops, and its intended
deployment by the Americans in Europe caused an uproar. The Russians apparently thought it was unfair that their vastly superior invasion forces could be defeated by a handful of troops armed with
nothing more exotic than howitzers and a few rockets.

‘The fact that the weapon only had defensive potential and so would only be used to kill the Russian hordes if those same Russian hordes first swept into Europe riding main battle tanks
was deemed to be irrelevant. The Americans didn’t deploy the weapon, although they did stockpile them in America to be used in the event of hostilities over here.’

‘And the Russians? Did they build any?’

Hillsworth nodded. ‘Of course they did. In the nineteen eighties they announced that they had built and tested neutron weapons. What the state of play is now I have no idea, but I strongly
suspect that somewhere in Russia some new kind of neutron bomb has been tested in the fairly recent past.’

‘Why is that, Professor?’ Richter asked, sitting forward slightly in the chair.

‘Because you’re here, sitting in my chair drinking my coffee and eating my biscuits and telling me a pack of lies about American designs for a super-bomb.’

‘Oh, yes?’ Richter said.

The professor smiled. ‘I’m not an idiot, Mr Richter. I know about Anglo-American co-operation in defence projects – apart from anything else I’m a member of one of the
Steering Committees – and if our cousins across the sea were developing a new weapon I promise you I would know about it. I don’t, so therefore they’re not, but the Russians
probably are. QED.’

‘Ah,’ Richter said, and drank the rest of his coffee. He reflected that you don’t get to become a professor at the age of thirty-two, which Hillsworth had achieved, without
being a pretty sharp cookie, but Richter somehow hadn’t expected quite this degree of sharpness. ‘Without wishing to confirm or deny—’ Richter started in his best Civil
Service voice, but Hillsworth interrupted.

‘Let me finish it for you,’ Hillsworth said. ‘I’ve heard it often enough. In brief, you are not prepared to confirm the source of your information, nor the quality of
that information, nor even, if pushed, the existence of that information. Right?’ Richter nodded. ‘In short, you’ve heard a story, or seen some kind of report, and you want an
independent opinion as to its veracity?’

‘Yes.’

Hillsworth shook his head. ‘I don’t know why you didn’t say that at the beginning instead of going all round the houses and sitting through a rather boring lecture on basic
nuclear weapon theory. I suppose you enjoy all the cloak and dagger aspects of it.’

Richter nodded again, somewhat sheepishly. ‘We like to keep in practice, Professor,’ he said. ‘OK, having cleared the air, is it possible that the Russians have managed to
develop a strategic neutron bomb?’

‘Anything’s possible, I suppose,’ Hillsworth said. ‘But there’s one very obvious problem if they have developed such a weapon and decide to re-arm with
it.’

‘Yes,’ Richter prompted. ‘What’s that?’

‘Well, if they have, the Russians would obviously place themselves at a very severe disadvantage in any future nuclear exchange. But,’ Hillsworth added, ‘there are three other
aspects about this that might be relevant to your enquiry. First, does the name Sam Cohen mean anything to you? Second, what do you know about America buying Russian weapons-grade plutonium? And
have you ever heard of red mercury?’

Hammersmith, London

Richter reached Hammersmith just after six thirty, parked the Escort in the Transport Pool’s underground garage, checked in with the Duty Officer, then went straight
up to Simpson’s office. Simpson was sitting at his desk, studying a file, which he snapped shut when Richter walked in.

‘Well?’ he demanded.

Richter sat down heavily in the chair in front of the desk. ‘It’s like this,’ he said, and started to explain what the professor had told him.