Delivery systems / means of delivery

Means of delivery are necessary to transport nuclear, biological and chemical weapons to the target. There are different kinds of means of delivery: Pieces of artillery, artillery shells, missiles, cruise missiles or torpedoes. Not all systems are equally suited for the different kinds of weapons of mass destruction: long-range ballistic missiles, for instance, cannot be used to transport biological weapons. Depending on from where they are deployed, delivery systems can be categorized into land-, air- and sea-based systems or, depending on their function, in air defence, sea- or land-based cruise missiles. There are various means of delivery for nuclear devices: Short-range, medium-range, long-range ballistic missiles and intercontinental missiles as well as submarine-based ballistic missiles, air-based cruise missiles or cruise missiles engaging targets on land.

Biological warfare agents

Biological warfare agents are pathogens or natural toxins that are used to weaken, damage, hurt or kill people, animals, plants or materials. They can be bacteria, viruses, spores or toxins. There are about 200 potential warfare agents listed as biological weapon, but only 12 of these are most likely to be used in an attack with a biological weapon as they spread easily, guarantee easy contamination and cause large numbers of deaths. The combination of a biological warfare agent and a delivery system results in a biological weapons.

The most effective and only feasible protection against the use of biological weapons during a war is to strengthen existing treaties and to stop the buildup of biological weapons capacities.

Biological Weapons Convention

The international Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons and on their Destruction - B(T)WC bans the development, production and stockpiling of biological weapons for military use. The Convention was developed by United Nations member states and opened for signature in 1972. It entered into force in 1975 and can be considered a further step towards the elimination of biological weapons—the first having been the Geneva Protocol of 1925 that only banned the use of biological weapons as a method of warfare—forbidding research (with the exception of defensive research, see infotext), production and stockpiling of these weapons.

All signatory states have committed themselves to destroying all stockpiles. A drawback of the Convention is that no verification measures have been agreed on. It has also been impossible so far to incorporate disclosure requirements and controls into the Treaty through an additional protocol. By 2012, 165 countries had ratified the Convention.


Bioterrorism is a variant of terrorism that uses biological weapons. A bioterrorist attack could either be carried out directly against population or the economic and ecological structure of a society. The most well-known bioterror attack is that by members of the Bhagwan Shree Rajneesh sect in The Dalles, Oregon State, in 1984, who contaminated food with salmonella, in which 751 people contracted food poisoning but no-one died. Another case was that of the so-called Amerithrax attacks (2001, infecting 22 people of whom five died; carried out most likely by people having connections to the US-American bioweapons research programme itself). As a matter of course, one can never totally rule out a bioterrorism attack. Previous experience, however, suggests that fears of the much-evoked bioterrorist are often exaggerated.

Chemical warfare agents

Chemical warfare agents are chemicals that, on the grounds of their chemical effects on the metabolic processes of the human or animal body can cause the death, a temporary inability to act or can permanently damage people or animals. These agents are produced artificially and spread over the battlefield mostly by artillery shells or spraying devices. In the past, these chemicals were gaseous; nowadays, they mostly consist of liquids (aerosols); solid materials are rare. The effect of a toxic agent can either be brief (up to four hours) or more long-term over many weeks until it vanishes. Due to the devastating effects, the use of such chemicals was forbidden by the Chemical Weapons Convention. A chemical weapon is the result of the combination of a chemical agent and a delivery system.

Chemical Weapons Convention

The Chemical Weapons Convention outlaws the development, production, possession, proliferation, stockpiling and use of chemical weapons in military operations. The convention was adopted in 1992 and entered into force in 1997. All signatory states committed themselves to flag all stocks as well as ammunition and machines for their production and to destroy these by the end of 2012. The Organisation for the Prohibition of Chemical Weapons (OPCW) in The Haague supervises this process. By 2010, 188 countries had signed the Convention, only six countries have so far refused to sign.

Defensive research

The UN Biological Weapons Convention explicitly forbids any research, production and stockpiling of biological weapons. But the Convention permits further research on pathogens that could potentially be used as weapons “for prophylactic, protective or other peaceful purposes” (Article I). The development of any anti-virus presupposes that there is a virus that must be identified and neutralized. In the field of biological weapons, in particular, it is therefore extremely difficult to clearly draw the line between offensive and defensive research as foreseen by the Convention. An effective inspection of whether the biological weapons convention is adhered to or not is therefore extremely difficult.

Dirty bomb

With a "dirty bomb" (also called radiological dispersal device) radioactive material is dispersed over a certain area and contaminating the environment by detonating conventional explosives. There is no nuclear fission, like in an atomic bomb. The radiological materials do not influence its explosive force. The views on the actual dangers of such a bomb differ, but the psychological effects of a bomb contaminated with radioactivity alone would be immense.

Dual -use

Dual -use goods are goods, software and technology that can be used for both civilian and military applications and/or can contribute to the proliferation of Weapons of Mass Destruction (WMD).

To be able to uphold international arms control policies, a list of dual-use goods is drawn up on a regular basis in the framework of the Wassenaar-Arrangement that are subject to special export licenses.

Nuclear energy and related technologies have the capacity of dual-use, as there is no clear separation between the civilian and military use of nuclear energy. This is why the danger of proliferation of many technologies and installations used for civilian purposes or research cannot be ruled out. Uranium enrichment facilities, for instance, can be used to produce fuel for nuclear power plants but also as a source for fissile material for nuclear weapons.

Highly enriched uranium (HEU)

To use uranium as fuel for nuclear power plants but also as fissile material in nuclear weapons, the uranium isotope -235, which only occurs in small quantities naturally, must be enriched. This is what uranium enrichment plants are for.

Is the content of the fissile isotope uranium -235 higher than 20 per cent, one refers to it as highly enriched uranium - HEU. To be able to use uranium for nuclear weapons, its content of the fissile uranium isotope -235 must be increased to at least 85 per cent. Only then does one refer to it as weapon-grade uranium. Highly enriched uranium is also used to fuel nuclear submarines. As HEU can be used both for civilian and military purposes, it is a so-called dual-use item.

Lethal dose

The amount of a drug or type of radiation that if administered to an animal or human will prove fatal. The measurement 'lethal dose' has been used since 1927 and is often only a guide value as tests on animals are not representative for humans. It is the calculated as the average of a representative population. A lethal dose for humans depends on the individual; weight, size, age or illness can be influencing factors.

Mustard gas

Mustard gas is the common name for 1-Chloro-2-[(2-chloroethyl)sulfanyl]ethane and is a warefare agent that is a blistering agent. Its name goes back to not fully cleaned gas that smelled of mustard or garlic. The gas was produced in 1822 for the first time and was first used as a warfare agent in 1916. Mustard gas was used during World War I and II as well as in various other conflicts. The chemical agent severely burns the skin, causing large blisters to form and affects the lungs when breathing it in.

Non-Proliferation Treaty

The Treaty on the Non-Proliferation of Nuclear Weapons (Non-Proliferation Treaty - NPT) is an international Treaty that entered into force in 1970.

By August 2016, 191 states had ratified the Treaty, agreeing that they would never acquire nuclear weapons, that they would not pass on the knowledge and technology needed to build a nuclear weapon and to only use nuclear technology for peaceful purposes and to eliminate existing nuclear weapons.

The Treaty recognizes five countries that had produced and tested nuclear weapons or other nuclear devices before 1 January 1967, as nuclear-weapon states: China, France, Great Britain, Russia and the United States. They have been granted the right to possess nuclear weapons, under the condition that they reduce their stocks. All other states are only permitted to acquire nuclear technology and material if the IAEA (International Atomic Energy Agency) is allowed to verify locally the exclusive peaceful purpose of the respective nuclear program.

Three countries that own nuclear weapons have not ratified the NPT: India, Israel and Pakistan. North Korea, which had acceded in 1985, withdrew from the Treaty in 2003. India, Israel and Pakistan are tolerated and/or indirectly recognized as nuclear weapons states outside of the Treaty. This is mirrored in the fact that they are trading partners for civilian nuclear projects and also shows one conflict potential of the NPT. Another potential for conflict is the unwillingness of the nuclear weapon states to reduce their stocks.

Nuclear disarmament treaties / Non-Proliferation Treaties

A number of international treaties' intention is to hinder and stop the proliferation of nuclear weapons. One of these treaties is the Treaty on the Non-Proliferation of Nuclear Weapons (Non-Proliferation Treaty - NPT) that entered into force in 1970. The Comprehensive Nuclear-Test-Ban Treaty forbids and kind of nuclear weapons tests and all other forms of nuclear explosions; is has, however, not yet come into force.

As the Treaty does not give a definition of 'nuclear test', it is controversial whether subcritical nuclear tests (see definition below), too, are forbidden.

There are various disarmament treaties between the two main nuclear weapons states, the United States and Russia, in particular. In 2002, former US President George W. Bush and Russia's President Vladimir Putin signed the SORT-Treaty (Strategic Offensive Reductions Treaty).

Nuclear power plants

Nuclear power plants generate electricity by a controlled fission or fusion of nuclear material. A nuclear power plant mostly consists of multiple reactors. In commercial nuclear power plants, the generated thermal energy is transformed into electricity in various ways. There are different types of reactors, such as light water reactors, heavy water reactors, graphite-, breeder- and molten salt reactors. Depending on the type, they either use low enriched or higher enriched uranium, or mixed oxide (MOX - a mixture of uranium oxide and plutonium oxide) as fuel.

Nuclear tests

Nuclear tests are conducted in the course of research on nuclear weapons and the behaviour of nuclear material under special circumstances.

One has to differentiate between critical and sub-critical tests. The first test, requires the minimum quantity necessary for a nuclear chain reaction (also called critical mass). The following explosion first results in an immense thermal heat wave, followed by a destructive blast wave and a nuclear radiation wave that scorches or contaminates living beings with radiation.

Subcritical tests, however, only use a small amount of weapons-grade, fissile material that is combined with (25 to 250 kg) explosives and triggered below the ground (about 300m depth). There is no nuclear chain reaction and no measurable release of radiation. It is not clear whether subcritical nuclear tests are nuclear tests according to the NPT and therefore banned. The United States and Russia continue to carry out subcritical tests and argue that they have to investigate the behaviour of ageing nuclear weapons. The 27th subcritical test was carried out on 5 December 2012 by the United States in the framework of the Stockpile Stewardship Program.

Nuclear umbrella

The nuclear umbrella is a term for the protection of non-nuclear weapons states by nuclear weapons positioned in those states by nuclear weapons states.

At the time of the Cold War, NATO and the former Soviet Union, the stationing of nuclear weapons was considered a necessary strategic protection. The largest part of the nuclear weapons in Europe was withdrawn after the end of the Cold War in the context of the German reunification and the unilateral initiatives of US President George W. Bush, Mikhail Gorbachev and Boris Yeltsin.

The technical aspects of the NATO system of nuclear sharing in NATO are controversial both politically and legally. The European countries that participate in this system are non-nuclear members of the Non-Proliferation Treaty (NPT) and have committed themselves under international law not to control nuclear weapons.

Nuclear weapons

Nuclear weapons are weapons of mass destruction whose destructive potential stems from the release of energy resulting from nuclear fission or fusion. To produce a nuclear weapon, either highly enriched uranium or separated plutonium is needed. Depending on the bomb size and the location of the explosion (in the air or on the ground), one single nuclear bomb can contaminate and/or destroy large areas and kill vast amounts of people. So-called radiological dispersal devices ('dirty bombs') do not fall under the category of nuclear weapons, as their destructive power stems from conventional explosives that scatter radiological material without causing either fustion or fission.

Nuclear weapons have so far only been used twice, in 1945, when the United States dropped one atomic bomb each over the Japanese cities of Hiroshima and Nagasaki.

Operational / military doctrine

A doctrine is a military guideline that combines strategies with requirements, difficulties and procedures during military operations. These guidelines prescribe a concept for various requirements of the military from which potential solutions are developed for each individual case. The doctrines must be adjusted to the current technical state-of-the-art due to the changed tactics. Possible content of a doctrine, for instance, are defence policy and the task of the armed forces.


Natural plutonium deposits are only very small; it is, however, unavoidably created in larger quantities in fuel rods in nuclear power plants as a by product of neutron capture and beta decay, where some of the neutrons released by the fission process convert uranium-238 nuclei into plutonium-239. In these fuel rods, a mixture of various elements and isotopes is created when they are spent, amongst them the plutonium isotope-239, which is particularly fissile and therefore suited as nuclear explosive. Weapons-grade plutonium is defined as concentration of 90 per cent plutonium -239 and more.

There are differing estimates as to how many kilogrammes of weapons-grade plutonium is needed at minimum to build an atomic bomb. It seems that between one and eight kilogrammes are necessary at least, depending on technical know-how and equipment.

The atomic bomb dropped over Nagasaki in 1945 used plutonium as fissile material.


The spread of weapons of mass destruction is called proliferation. As weapons of mass destruction constitute a grave danger for international security, the international community of states aspires to have the best possible control over these weapons. In general, one assumes that the control of such weapons is easier the less countries are in the possession of weapons of mass destruction. To curb the possession of these weapons, there are various tools, such as arms exports controls, arms control policies and arms control treaties, disarmament and support for disarmament, or diplomatic measures up to sanctions.

Reprocessing plants

Fuel rods of a nuclear power plant can only be used for a few years. After that, they are spent and are taken out of the reactor. In reprocessing plants, the remaining fissile elements uranium and plutonium contained in the spent fuel rods are separated chemically from other components and can be used again.

The positive effect of reprocessing is that highly radioactive materials can be re-used. The negative effect is that large amounts of radioactive waste are produced that cannot be re-used. Still today, it is unclear how and where radioactive waste can be stored safely. The spent fuel rods must be transported across great distances, via land and sea to arrive at the reprocessing plants. The reprocessing process creates separated, weapons-grade plutonium, the most important source for nuclear weapons.

Riot control agents (tear gas)

Tear gas (2-chlorobenzalmalononitrile) is a lacrimator in form of an aerosol (a colloid of fine solid particles or liquid droplets in gas, similar to a deodorant spray) that, besides other irritants, is used worldwide by the police to disperse crowds, for instance, during (unwanted) large-scale rallies. People react differently to this irritant; in general, it leads to respiratory tract irritation, nausea and increased lacrimation (hence the name). In high dosages, like the use in closed rooms, it can cause burns, the disintegration of skin, oedemas in the lungs and, in individual cases, result in death. For this reason, its use is highly controversial.

The Chemical Weapons Convention forbids the use of CS gas, and other riot control agents as a method of warfare (Article I, Section 5).

Strategic and tactical nuclear weapons

The difference between strategic and tactical nuclear weapons played an important role for the United States and USSR during the Cold War. Tactical and strategic nuclear weapons differed in their range and the explosive force of the nuclear warhead. Strategic nuclear weapons were those weapons with which the United States and the USSR would have been able to target each other directly and that would have had great explosive force. Tactical weapons, on the contrary, were to be used in the battlefields of Europe or Korea with a smaller or larger explosive force, preventing a global nuclear war.

Types of chemical weapons

The first chemical weapons in World War I consisted of known toxins from chemical industry (mostly chlorine and phosgene) that were filled in containers and used against the enemy on the front lines. Later on, chemists developed warfare agents specifically for the use by the military. Usually, these chemical agents are divided according to their pharmacological-toxic effects into blood-, blistering-, choking-, nerve- and psychopharmacological agents as well as so-called mask breakers, riot control agents, toxins used for sabotage and environmental toxins.


99.3 per cent of naturally occurring uranium consists of its isotope U-238, small quantities of uranium -235 (0.7 per cent) as well as traces of uranium-234. Uranium -235 is the easiest fissile uranium isotope and is therefore used as fuel element in nuclear reactors and for atomic bombs. 100. Minerals containing uranium are extracted from mines and traded as uranium ore or concentrate, also known as 'yellow cake'.

Plutonium and uranium are the only naturally occurring chemical elements with fissile isotopes that trigger a nuclear fission chain reaction.

Uranium enrichment plants

Uranium enrichment plants are important installations for the generation of electricity. In these plants, the traces of the uranium isotope-235 contained in the uranium ore are enriched to make it usable for nuclear reactors or nuclear weapons.

There are different methods of separating the uranium-235 from the more common uranium -238 and to enrich it. Commercially, only two methods are used: Gas diffusion or the gas centrifugal system. Both methods use the fact that uranium -235 and uranium -238, which are chemically identical, differ in their mass; uranium -235 is about one per cent lighter than uranium-238.

To run commercial nuclear reactors, uranium-235 must be enriched by 3.5 per cent; for research reactors by about 20 per cent and nuclear weapons need a share of uranium-235 of 90 per cent. To achieve such a high level of enrichment, often the frequency must be increased.

Weapons of mass destruction

There is no generally recognized definition for weapons of mass destruction or one that is binding under international law. The term is mostly used as the collective term for nuclear, biological and chemical weapons and their delivery systems. Compared to conventional weapons, their spacial power of destruction, and killing force is also extremely high.

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