Gas Warfare

Chemical warfare (CW) involves using the toxic properties of chemical substances as weapons. This type of warfare is distinct from nuclear warfare, biological warfare and radiological warfare, which together make up CBRN, the military acronym for chemical, biological, radiological, and nuclear (warfare or weapons), all of which are considered "weapons of mass destruction" (WMDs), a term that contrasts with conventional weapons.

The use of chemical weapons is prohibited under customary international humanitarian law.

Definition

Chemical warfare is different from the use of conventional weapons or nuclear weapons because the destructive effects of chemical weapons are not primarily due to any explosive force. The offensive use of living organisms (such as anthrax) is considered biological warfare rather than chemical warfare; however, the use of nonliving toxic products produced by living organisms (e.g. toxins such as botulinum toxin, ricin, and saxitoxin) ''is'' considered chemical warfare under the provisions of the Chemical Weapons Convention (CWC). Under this convention, any toxic chemical, regardless of its origin, is considered a chemical weapon unless it is used for purposes that are not prohibited (an important legal definition known as the General Purpose Criterion).

About 70 different chemicals have been used or stockpiled as chemical warfare agents during the 20th century. The entire class known as Lethal Unitary Chemical Agents and Munitions have been scheduled for elimination by the CWC.

Under the convention, chemicals that are toxic enough to be used as chemical weapons, or that may be used to manufacture such chemicals, are divided into three groups according to their purpose and treatment:
* Schedule 1 – Have few, if any, legitimate uses. These may only be produced or used for research, medical, pharmaceutical or protective purposes (i.e. testing of chemical weapons sensors and protective clothing). Examples include nerve agents, ricin, lewisite and mustard gas. Any production over 100 g must be reported to the OPCW and a country can have a stockpile of no more than one tonne of these chemicals.
* Schedule 2 – Have no large-scale industrial uses, but may have legitimate small-scale uses. Examples include dimethyl methylphosphonate, a precursor to sarin, and thiodiglycol, a precursor chemical used in the manufacture of mustard gas but also widely used as a solvent in inks.
* Schedule 3 – Have legitimate large-scale industrial uses. Examples include phosgene and chloropicrin. Both have been used as chemical weapons but phosgene is an important precursor in the manufacture of plastics and chloropicrin is used as a fumigant. The OPCW must be notified of, and may inspect, any plant producing more than 30 tons per year.

History

Simple chemical weapons were used sporadically throughout antiquity and into the Industrial age. It was not until the 19th century that the modern conception of chemical warfare emerged, as various scientists and nations proposed the use of asphyxiating or poisonous gasses.

Multiple international treaties were passed banning chemical weapons based upon the alarm of nations and scientists. This however did not prevent the extensive use of chemical weapons in World War I. The development of chlorine gas, among others, was used by both sides to try to break the stalemate of trench warfare. Though largely ineffective over the long run, it decidedly changed the nature of the war. In many cases the gasses used did not kill, but instead horribly maimed, injured, or disfigured casualties. Some 1.3 million gas casualties were recorded, which may have included up to 260,000 civilian casualties.

The interwar years saw occasional use of chemical weapons, mainly to put down rebellions."Chemical Weapons" in ''Historical Dictionary of Ethiopia'', 2d ed. (eds. David H. Shinn & Thomas P. Ofcansky: Scarecrow Press, 2013). In Nazi Germany, much research went into developing new chemical weapons, such as potent nerve agents. However, chemical weapons saw little battlefield use in World War II. Both sides were prepared to use such weapons, but the Allied powers never did, and the Axis used them only very sparingly. The reason for the lack of use by the Nazis, despite the considerable efforts that had gone into developing new varieties, might have been a lack of technical ability or fears that the Allies would retaliate with their own chemical weapons. Those fears were not unfounded: the Allies made comprehensive plans for defensive and retaliatory use of chemical weapons, and stockpiled large quantities."Paxman and Harris"
Pakistan p. 132–135.Callum Borchers
Sean Spicer takes his questionable claims to a new level in Hitler-Assad comparison
''The Washington Post'' (April 11, 2017). Japanese forces used them more widely, though only against their Asian enemies, as they also feared that using it on Western powers would result in retaliation. Chemical weapons were frequently used against Kuomintang and Chinese communist troops. However, the Nazis did extensively use poison gas against civilians in The Holocaust. Vast quantities of Zyklon B gas and carbon monoxide were used in the gas chambers of Nazi extermination camps, resulting in the overwhelming majority of some three million deaths. This remains the deadliest use of poison gas in history.Patrick Coffey, ''American Arsenal: A Century of Weapon Technology and Strategy'' (Oxford University Press, 2014), pp. 152–154.James J. Wirtz, "Weapons of Mass Destruction" in ''Contemporary Security Studies'' (4th ed.), ed. Alan Collins, ''Contemporary Security Studies'' (Oxford University Press, 2016), p. 302.

The post-war era has seen limited, though devastating, use of chemical weapons. During the Vietnam War, between 1962 and 1971, the United States military sprayed nearly 20,000,000 U.S. gallons (76,000 m³) of various chemicals – the "rainbow herbicides" and defoliants – in Vietnam, eastern Laos, and parts of Cambodia as part of Operation Ranch Hand, reaching its peak from 1967 to 1969. Some 100,000 Iranian troops were casualties of Iraqi chemical weapons during the Iran–Iraq War. Iraq used mustard gas and nerve agents against its own civilians in the 1988 Halabja chemical attack.On this day: 1988: Thousands die in Halabja gas attack
BBC News (March 16, 1988). The Cuban intervention in Angola saw limited use of organophosphates. The Syrian government has used sarin