When the first nuclear bomb was detonated in 1945, it was an achievement that had been made possible by remarkable scientific discoveries and hastened by the Second World War. Scientists from many nations, striving since the beginning of the century to understand the nature of matter, had unwittingly helped to prepare the way. The discovery that splitting the nucleus of a heavy element into two positively charged nuclei of lighter elements which would repel each other and give off massive amounts of energy pointed to the possibility of producing a nuclear fission weapon, or atomic bomb, with greater energy and explosive power than the weapons of previous eras.'
One form of reaction used in nuclear weapons, and the only form used in the early atomic weapons, is fission - the splitting of the nucleus of the heavy elements into two nuclei of lighter elements. Fission is caused by the absorption of an unattached neutron into a nucleus and results in the liberation of other neutrons, typically two or three. The process occurs naturally and continually in fissile material (i.e. uranium 235 or plutonium). To achieve this state the proper elements must achieve a 'critical' point where the ratio of mass to surface area is increased beyond a certain level. The instantaneous liberation of neutrons which accompanies the fission process can produce a self sustaining chain reaction accompanied by the rapid release of enormous amounts of energy, and a nuclear detonation results (Figure 1). To produce this massive explosion it is necessary to compress the fissile material suddenly (explosives are commonly used for this) and then hold it together and prevent the liberated neutrons from escaping as long as possible by means of a neutron-reflecting container (Figure 2).' When the container reaches its threshold, the energy is released.
The yield of a nuclear weapon is a measure of explosive energy it carries. It is the usual practice to state the yield in terms of a quantity of TNT that would generate a comparable amount of energy when it explodes. Thus, a one-kiloton nuclear weapon is one which produces the same amount of energy in an explosion as does one kiloton, or 1,000 tons, of TNT. Similarly, a one-megaton weapon would have the energy equivalent of one million tons of TNT. The earliest bombs, such as the two dropped over Japan in 1945 released roughly the same quantity of energy as 20,000 tons of TNT. Since that time, much more powerful weapons, with energy yields in the megaton range, have been developed. As a general rule most fission devices have powers in the range from about I kiloton up to about 22 kilotons, but fusion devices have powers measured in megatons. A typical fusion
device could have IO megatons of power and some can generate 50 megatons or more. These awesome figures show how science has created a powerful monster in the form of nuclear weapons.
The effects that a nuclear explosion has on people, buildings, and the environment can vary greatly, depending on a number of factors. These factors include weather, terrain, the point of explosion in relation to the earth's surface, and the weapon's yield. This section describes the possible effects of a large nuclear device. The weapon's explosion would produce three basic phases: a blast wave, thermal radiation, and residual nuclear radiation. The dispersment of these phases can be seen in Figure 4.
The explosion begins with the formation of a 'fireball', which consists of a cloud of dust and of extremely hot gases under very high pressure. A fraction of a second after the explosion, the gases begin to expand and form a blast wave. This wave moves rapidly away from the 'fireball' like a moving wall of highly compressed air. As the wave moves for-ward, it creates overpressure, which is atmospheric pressure above the normal level (Figure 3). A one-megaton explosion can produce enough overpressure to destroy most buildings within one mile of ground zero. The blast wave is also accompanied by strong winds. These winds may reach speeds of 400 miles per hour. The blast wave and wind from this bomb probably would kill the majority of the people within three miles of ground zero and injure anyone within six miles.'
The second effect is thermal radiation which vaporizes and bums whatever it meets. When the nuclear device is set off the immediate result is an enormous amount of heat produced in less than one millionth of a second. The heat-energy has to expand rapidly, and as it does so it vaporizes anything in its immediate vicinity, including the casing of the device itself. The expansion is so great that the explosion produces a fireball which emits its energy in the form of heat and light to actually produce the thermal destructive effects. Thermal radiation consists of ultraviolet, visible, and infrared radiation given off by the 'fireball'.' The ultraviolet radiation is rapidly absorbed by particles in the air, and so it does little harm. However, the visible and infrared radiation can cause eye injuries as well as skin bums called flash bums. Between 20 and 30 percent of the deaths at Hiroshima and Nagasaki resulted from flash bums.' A person can be shielded from the effects of thermal radiation by solid non-transparent objects like walls, trees, and rocks. However, thermal radiation generated by a one-megaton explosion can produce second-degree bums to exposed human skin up to 11 miles from the point of detonation.' Thermal radiation also can ignite such highly flammable materials as newspapers and dried leaves. The burning of these materials can lead to large fires. In a widespread nuclear war, the fumes from these fires could pollute the atmosphere. This would cause a nuclear winter where there will be a decrease in the amount of sunlight and the temperature will drop.
Residual nuclear radiation is given off later than one minute after the explosion. Residual radiation created by fission consists of gamma rays and beta particles (electrons). Residual radiation produced by fusion is made up primarily of neutrons." Residual radiation strikes particles of rock, soil, water, and other materials that make up the mushroom-shaped cloud. As a result, these particles become radioactive. When the particles fall back on earth, they are known as fallout. The closer an explosion occurs to the earth's surface, the more fallout it produces. Early fallout consists of heavier particles that reach the ground during the first 24 hours after the explosion. These particles fall mostly downwind from ground zero. Early fallout is highly radioactive and will kill or severely damage living things. Delayed fallout consists of tiny, often invisible, particles that may eventually fall in small amounts over a large area of the earth. Delayed fallout causes only long-term radiation damage to living things.
There is also one other little-known effect of the detonation of a nuclear device and that is the one known as the electromagnetic pulse or EMP. This is a byproduct of the immediate energy release from a detonated nuclear device which, as well as the other effects mentioned above, also has the ability to alter the electrical properties of electrons in the nearby atmosphere. This can produce intense electrical and magnetic fields which generate so much energy that they can severely affect electronic based equipment and electrical and radar transmissions to the point of destroying equipment circuits, components, and communications." The effects of EMP diminish sharply with distance from the point of detonation but can still cause damage at ranges greater than those for the other three major phases.
All of these effects present terrifying consequences by themselves, together they display the spectrum. of terror that nuclear weapons contain.
Methods of Delivery
The following is a remark by former Secretary of Defense Les Aspin about the modem nuclear threat, "The old nuclear danger we faced was thousands of Soviet warheads. The new nuclear danger we face is perhaps a handful of nuclear devices in the hands of rogue states or even terrorist groups. The engine of this new danger is proliferation." 1 2 Equally alarming as the effects of nuclear weapons is their versatile means of attack. They could be launched from another continent or simply placed in a car and discretely parked beneath a target.
For strategic applications, nuclear weapons can be delivered by land or sea launched ballistic missiles, or by long-range bomber aircraft. For tactical uses, nuclear weapons may be delivered by short range missiles, combat aircraft carrying bombs, artillery shells, naval torpedoes/depth charges, or land mines." Nuclear missiles, like the one shown in Figure 8, continue to make up a substantial proportion of the strategic forces of the major powers (US, Russia, UK, China, and France). But outside the major power context, combat aircraft modified to carry nuclear payloads offer the most widely available nuclear delivery platform for lesser powers or rogue regimes. In very general terms, it is easier for a rogue regime of Third World nation to build a nuclear device for aircraft delivery than it would be to construct a warhead for a ballistic missile, which requires greater technical capability and testing capacity. The bombs used by the United States in the Second World War were delivered by aircraft. It is widely assumed, for example, that the three undeclared nuclear powers, Israel, India, and Pakistan, have the ability to deliver nuclear weapons by combat aircraft. But it is not clear that India or Pakistan have succeeded in arming nuclear warheads for delivery by missile.
There has also been discussion of the nuclear "suitcase bomb" or other terrorist delivered weapons. A terrorist could try to purchase a nuclear weapon, as the Japanese Aum Shinrikyo cult apparently tried to do in Russia, or build a crude device on its own. In the following passage, Kenneth Waltz comments on this subject.
With the devolution of nuclear weapons to three of the parts of the former Soviet Union, with shaky control of the nuclear weapons materials in Russia, with the revelation in 1994 that the United States had lost track of some of its nuclear materials, with increased numbers of countries able and perhaps willing to sell components needed to develop nuclear capability to countries that lack them, and with a flourishing market in systems for the delivery of weapons, fear has grown that terrorists may obtain nuclear explosives and means of placing them on targets they choose. The worry is real, especially if terrorists are eager to have nuclear explosives and are backed by a state bent on disrupting international society."
The potential targets of these weapons include: hardened military targets and key political and military control and command centers; major troop and armor concentrations; dispersal areas; logistics centers; air bases; ports, as well as key infrastructure installations (oil facilities, desalination plants, etc.)." Major civilian population centers may be targeted in order to force dispersal of population, achieve wholesale terror and destroy the political and economic infrastructure of the nation.
Our defenses against any form of nuclear attack are insufficient due to the destructive force of even a single nuclear weapon. For example, while China's nuclear weapon program was just coming into fruition in 1974, they had the capability of producing several nuclear weapons for military use. It is estimated that if China had strategically attacked the top ten cities of the USSR they would have destroyed 25 percent of its industrial capacity and 25 percent of its urban population." Today, nuclear weapons can still be the equalizer against superior forces. But today it is the United States that has unmatched military power, and it is our potential adversaries who may attain nuclear weapons. We are the ones being equalized.
What chance would the United States have at stopping an isolated terrorist attack using nuclear weapons? Fat Man was the name of the atomic bomb dropped over Nagasaki in 1945 and can be seen in Figure 9. It was 60 inches in diameter, 12 feet in length, and weighed 10,300 lbs. Even an ancient artifact of the nuclear age like Fat Man would be able to be transported on a commercial truck but technology would allow today's bomb to be lighter and more efficient. It is conceivable that terrorists with access to modern technology could ascertain a weapon that could easily be transported in a U-Haul truck. Importation is extremely plausible when you consider that in 1989 1,81 0,000 pounds of cocaine was imported into the United States with only ten percent of that vast amount being confiscated." How can the government possibly secure all points of entry into our country? A weapon could be brought into the US by boat or plane and then moved by truck to the designated target. With the proper design, the weapon could be configured to give off only low amounts of radioactivity and would be almost undetectable, even if our nation had protocols to check for levels of radiation. Figure 5 shows the results if a nuclear device in the 20 kiloton range were to be detonated in Washington DC. The outcomes are horrifying as second degree bums would be felt within a two mile radius and structural damage within a three mile radius. But the possibility exists that a small terrorist device could be used for blackmail purposes, sabotage, or to contaminate and cause chaos in a key target of a political adversary. It is important to understand that the existence of nuclear weapons has presented us with a variety of security issues.
While the military capabilities of nuclear weapons are amazing there are several limitations that might restrict their use. The technical difficulties and high cost of developing nuclear weapons means that few states other then the major powers are likely to obtain or build militarily significant amounts of nuclear weapons. The creation of nuclear material is difficult and risks failure or nuclear accident on friendly territory. The long lasting radiation effects of nuclear weapons may mean that the territory an attacker wishes to move across or occupy remains contaminated, necessitating the use of protective equipment and requiring substantial resources to be devoted to decontamination. An attack with nuclear weapons is also likely to cause a high number of civilian casualties and great collateral damage. Any government that used nuclear weapons would thus risk retaliation. This is one reason that terrorists may never resort to using nuclear weapons. Terrorists have some hope of reaching their long term goals through patient pressure and constant harassment. They cannot hope to do so through the carnage and retaliation that would result from a nuclear strike. A similar fear of retaliation is what created and maintained the balance of terror between the nuclear powers.
When the atomic bomb became a reality its creators realized the implications it would have on our world. They knew about the abilities of the weapon, how it was immensely more powerful than anything prior. They knew about the effects of the bomb, how radiation would cause not only death but disfigurement and disease. They knew that the technological requirements for atomic weapons would create an uneven playing field between the developed nations of the world. But scientists like Edward Teller pressed on for the creation of our nuclear age because they saw other possibilities (nuclear power) and had the hope that humanity would realize the peril that loomed over it. Whether by chance, fear, or intelligent restraint, nuclear weapons have only been used once in world military history and that one time has served as a reminder for the future. Now we must take the next step to end proliferation and begin dismantling. President Clinton directed the world's attention to nonproliferation during a speech before the LJN's general assembly in 1993. He said, "one of our most urgent priorities must be attacking the proliferation of weapons of mass destruction ... If we do not stem the proliferation of the world's deadliest weapons, no democracy can feel secure."" More generally, it is time to replace the inherited distinction between those countries with nuclear weapons and those without by a wider assertion that all nations should be on the same side-against nuclear danger-whatever their present degree of reliance on nuclear weapons. This last proposition clearly shows across the board disarmament is the best single guide for any country, both now and in the long run.
Bundy, McGeorge. Reducing Nuclear Danger. US: Council on Foreign Relations Inc., 1993. pg. 1-9.
Defense Counter proliferation Initiative (http://www.epnet.com) pg. 1-5.
Edwards, A.J.C. Nuclear Weapons: The Balance of Terror and Quest for Peace. New York: New York Press, 1986. pg. 10-42
Gander, T.J. Nuclear, Biological, and Chemical Warfare. London: Ian Allen Ltd., 1987. pg. 23-36
Sagan, Scott. Waltz, Kenneth. T'ne Spread of Nuclear Weapons. New York: WW Norton Corn., 1995.pg.22,94.
Teller, Edward. Our Nuclear Age. New York: Criterion Books, 1958. pg. 37-68.
War on Drugs (b-ttp://turnpike.net/ 'nr/bushwar.htm) pg. 5
Weiss, Ann E. The Nuclear Arms Race: Can We Survive It? Boston: Houghton Mifflin Corn., 1983. pg. 25-31.