CHAPTER TEN
Preventing Proliferation
NUCLEAR FISSION, IN which a tiny amount of mass is converted to a large amount of energy by splitting a big atom, is the basic power source of both nuclear power plants and nuclear weapons. But they are not the same thing, any more than using gasoline in your car is the same thing as dropping napalm, though both use the same basic chemistry.
If you hear the word nuke or see a protest sign reading “No Nukes,” do you think of nuclear weapons or nuclear power plants? It could be either, and that’s a problem. Nuclear weapons are extremely scary and dangerous, have killed hundreds of thousands of people historically, threaten billions more today, and do not have a useful purpose except possibly in a negative sense of deterring their use by others. Nuclear power, by contrast, has been extremely safe and has saved millions of lives through the displacement of coal and other deadly fossil fuels.
There are, nonetheless, connections between the two “nukes,” and we will need to take these into account if we are to successfully use nuclear power to help rapidly decarbonize the world.
One connection is historical. The United States and the Soviet Union mastered fission during World War II and the Cold War with the primary purpose of building a lot of big bombs. The nuclear power industry produced electricity, but in some places it also produced by-products that served as fissile material for nuclear weapons. The very earliest reactor designs were chosen to maximize the production of these elements—exactly the opposite of what we want now from reactor designs.
Uranium occurs naturally around the world, but in its natural form it contains only a little bit of the isotope1 needed for fission. Through great effort, with thousands of centrifuges feeding from one to another, it is possible to concentrate the potent variant of uranium enough to build a bomb from it. This is called uranium enrichment. This is what Iran was doing, for example, before the international deal that froze its enrichment program so that it couldn’t build nuclear weapons. Pakistan has also used centrifuges to build uranium bombs, and North Korea has done the same.
Figure 35. Uranium-enrichment centrifuges seized in 2003 en route to Libya, which had no civilian nuclear power program. Photo: US government, Y-12.
A second material suitable for building a bomb is certain isotopes of plutonium. Plutonium does not occur naturally but can be produced in a nuclear reactor as a by-product of splitting uranium atoms. This was the primary route to nuclear weapons for the great powers, including the United States. During World War II, the United States created both a uranium bomb and a plutonium bomb and dropped them on Hiroshima and Nagasaki, respectively.
The key task for preventing the spread of nuclear weapons is to keep these two materials—highly enriched uranium (HEU) and plutonium—away from new countries or nonstate actors. Obtaining plutonium is not too difficult if one has certain kinds of nuclear reactors. For example, Japan has a pile of it right now. But building a plutonium bomb is quite difficult. A terrorist couldn’t do it, and even a sizable country such as North Korea needs a concerted program over many years and using large budgets. By contrast, building a uranium bomb is much simpler, but obtaining HEU is difficult.
When nuclear power first emerged as a useful source of electricity around the world, the international community put in place strong governance structures to ensure the peaceful uses of nuclear materials. Above all, the countries of the world wanted to prevent a country from secretly diverting plutonium or HEU from a nuclear reactor into a weapons program. To this end, the world established the International Atomic Energy Agency (IAEA), an independent arm of the United Nations, with the mission of inspecting nuclear power programs around the world and making sure materials were handled safely and peacefully.
The IAEA has been remarkably effective. Its inspectors have the power to make intrusive inspections, to leave cameras in place watching what happens, to place seals on containers so that they can’t be secretly opened, and to interview scientists in order to make sure things are what they appear to be. At certain important locations, the IAEA has its own full-time staff and its own independent labs inside of nuclear facilities to ensure that complete and uninterrupted safeguards are in place.
It’s hard to keep nuclear secrets in today’s world. When Iraq’s Saddam Hussein was suspected of developing a nuclear weapons program, IAEA inspectors crawled all over the place and didn’t find anything only because Saddam had shut the program down years earlier. When Iran enriched uranium, the world found out about it. When North Korea made a deal to shut down its plutonium production but kept running a secret uranium-enrichment program, the world found out about it. (North Korea then withdrew from the IAEA in order to carry on.) When a Pakistani scientist sold uranium-enrichment technology to several countries, the world caught him at it. When Syria built a secret nuclear reactor, Israel bombed it.
Figure 36. IAEA inspectors installing monitoring equipment, Czech Republic, 2015. Photo: International Atomic Energy Agency.
Decades ago, it was widely feared and assumed that by now dozens of countries would have nuclear weapons, but this has not happened. Nine countries have them, including the problem case of North Korea, but proliferation has not gone beyond that.
The main reason more countries do not have nuclear weapons is that they have chosen not to. Dozens of countries have the ability, but they have concluded that the costs far exceed the benefits. Sweden once considered nuclear weapons but decided not to pursue them. Argentina and Brazil started in on an arms race, but stopped before either built its first weapon. South Africa actually built a nuclear weapon but then destroyed it and scrapped the program when apartheid ended.
These countries, and almost all others, belong to a treaty, the Non-Proliferation Treaty (NPT), that requires them to forgo nuclear weapons. The NPT/IAEA system has successfully decoupled nuclear power technology from the spread of weapons. The only nonmembers of the NPT (putting aside South Sudan, which has been in a civil war since its recent founding and has no nuclear interests) are India, Pakistan, and Israel—the three states that developed nuclear weapons after the original five were grandfathered into the treaty. In addition, North Korea belonged to the NPT but then withdrew from it, the only nation ever to do so, and built nuclear weapons.
In the past thirty years, the superpower arms race has gone into reverse, with the stockpiles of tens of thousands of nuclear weapons reduced on both sides by 75–80 percent. The scientific and engineering complexes that had been devoted to building weapons have now mostly shifted to dismantling them. This means that the civilian nuclear power industry now has less and less connection to the military, which no longer needs more plutonium. In fact, a lot of enriched uranium from dismantled Soviet warheads was watered down and used as fuel in civilian US nuclear reactors. From 1998 to 2013, about 10 percent of the electricity used in the United States came from 20,000 dismantled Soviet warheads.2 Additional uranium and plutonium from weapons has been converted for use as fuel in American and Russian civilian reactors and naval propulsion.3
Nuclear power has not been a factor in the proliferation of nuclear weapons to new countries.4 The countries that have refused to join the NPT, have kicked out IAEA inspectors, or have secretly built their own nuclear weapons have not done so using civilian nuclear programs. Neither Israel nor North Korea even has a civilian nuclear power program. As five experts on proliferation put it in 2000, “To date, commercial nuclear power has played little, if any, role as a bridge to national entry into the nuclear arms race, nor are there any known cases in which individuals or subnational groups have stolen materials from nuclear power facilities for use in weapons.”5
Actually, the creation of civilian nuclear power programs in a number of countries has served as a check on nuclear weapons proliferation. Countries with nuclear know-how have helped new countries to build and operate nuclear reactors for electricity, and those new countries in turn have signed the NPT and accepted the strict rules of the IAEA.6 This happened in South Korea, for example, in the 1970s, when it decided against having a bomb and instead turned to developing a civilian nuclear power industry under international supervision. Today, it is a model of affordable and safe nuclear power—even exporting power plants to the United Arab Emirates (UAE) recently—and still does not have a nuclear bomb despite the bad behavior of its threatening neighbor, North Korea.7
If the number of nuclear reactors in the world increases, and more countries host them, the international community can and should expand its efforts to ensure that reactor fuel does not get processed into potential bomb material.8 A key method to do this is to keep countries from building their own uranium-enrichment and fuel-reprocessing facilities. For reactor use, uranium has to be enriched from below 1 percent of the fissile type to 4–5 percent (known as low-enriched uranium, or LEU). LEU cannot be used for bombs. (The 2015 multinational agreement with Iran limits its uranium enrichment to 3.7 percent.)9 But countries that master enrichment methods themselves might be tempted to enrich uranium to above 90 percent (HEU) for weapons use. Countries that invest large sums in long-lived reactors want assurance of a supply of LEU, the fuel for the light-water reactors that predominate today. Hence, the international nuclear power regime provides LEU externally to countries that own reactors but not nuclear weapons.
The IAEA has recently created a physical LEU fuel bank that will assure countries of access to fuel in the event of unusual circumstances in which their regular supply is disrupted, but only when comprehensive IAEA safeguards are in place for that country. The bank, located in Kazakhstan and set to receive LEU in 2018, will have enough fuel to power a city for several years. It may never be needed but is intended to prove that countries with reactors do not need their own nuclear fuel-cycle infrastructure with its potential to be diverted for misuse.10 (Russia also operates its own physical LEU bank, and the United Kingdom offers a guarantee of LEU supply.) Kazakhstan, incidentally, is a model country that inherited about 1,500 nuclear weapons when the Cold War ended but got rid of all of them within a few years. It is also the world’s largest miner of uranium.
Figure 37. IAEA Kazakhstan LEU fuel bank, 2017. Photo: Courtesy of Nuclear Threat Initiative.
Further initiatives have been proposed to ensure nonproliferation in a world of growing nuclear power. In several proposed ways, the international community could internationalize the fuel cycle. For example, Daniel Poneman, an expert on nuclear fuel and proliferation, has proposed an Assured Nuclear Fuel Services Initiative that would guarantee reactor fuel at good prices to countries that commit to not seek enrichment or reprocessing capabilities. He argues that this approach would be more effective than current unilateral US efforts to impose stringent safeguards, which only lead buying countries to find fuel from less demanding suppliers.11
Incidentally, a source of confusion around nuclear power and weapons is the use of nuclear power for propulsion in some warships. These nuclear-powered ships may carry nuclear weapons such as missiles or may carry no nuclear weapons, and a non-nuclear-propelled ship may similarly carry nuclear weapons or not. There is no connection between the type of propulsion and the weapons on the ship. Naval nuclear propulsion was a clever accomplishment of Admiral Hyman Rickover in the early Cold War. He built nuclear reactors quickly and successfully to power submarines and aircraft carriers in particular. This concentrated power source allows these warships to remain at sea, including underwater, for long periods. Worldwide, nuclear-powered ships have logged more than 12,000 reactor-years of operation with 700 reactors, 200 of which are currently operating, and the last serious reactor accident was more than thirty years ago. (As with civilian reactors, the only lethal naval reactor accidents were in the Soviet Union, which had several in the period 1961–1985. The US Navy has operated 6,200 reactor-years with no known radiological incident.)12
A final consideration making nuclear proliferation easier to prevent is that countries are not fighting each other currently. Although the world’s countries are armed to the teeth, many conflicts simmer, and a war between countries could break out anytime—in 2018 the US–North Korea standoff was especially scary—such wars have become quite rare. All today’s active wars are civil wars, within countries. Historically, regular national armies fought against each other constantly. During the Cold War, the most destructive and deadly wars were between those national armies—the Korean War, India-Pakistan, and Iran-Iraq, for example. But today, the last such war was the invasion of Iraq in 2003, a decade and a half ago.13 Whole categories of warfare such as tank battles and major naval battles are also disappearing.
Figure 38. Interstate wars by decade. Data source: UCDP/PRIO Armed Conflict Dataset, version 17.2. Wars defined as armed conflicts with more than one thousand battle fatalities in the year. See Marie Allansson, Erik Melander, and Lotta Themnér, “Organized Violence, 1989–2016,” Journal of Peace Research 54, no. 4 (2017); and Nils Petter Gleditsch et al., “Armed Conflict, 1946–2001: A New Dataset,” Journal of Peace Research 39, no. 5 (2002).
These days, when two hostile countries skirmish, the violence tends to die down quickly rather than escalate to all-out war. Some frightening episodes have brought state armies into small-scale violent clashes, such as in Armenia-Azerbaijan, Ukraine-Russia, Cambodia-Thailand, and Israel-Lebanon in recent years. But cooler heads prevailed. In 2017 the Chinese and Indian armies performed a ritual standoff in a nearly inaccessible mountaintop area of Bhutan, in which they insulted each other and threw sticks. But a real war between China and India would be a disaster for both, and everyone seems to know this.
Of course, this state of nonwar between regular armies is fragile and could break down, but it does still contribute to an atmosphere in which countries do not feel great pressure to obtain nuclear weapons. Contrast this with the US decision to build the bomb during World War II when a huge war was going on and an enemy might get the bomb first. That kind of world, mercifully, is not the world we now live in.
As we will discuss in Chapter 12, new nuclear power designs in the coming years will make it even harder to divert material for military use. Meanwhile, we can be reassured by an impressive record over the decades since nuclear technology was developed. As with accident safety, so with proliferation: there is always plenty to worry about, but in practice the system works. With continuing effort, we can keep risks extremely low.