Major CW Incidents Before 1945
German battery of chlorine gas cylinders being prepared for an attack, awaiting the right weather conditions to prevent blowback; similar to the arrangement at Hill 60 in May 1915
World War 1
Gas Attack by the German Army on the Osowiec Fortress, Poland, during the 1st World War
Modern chemical warfare (G) began on 22 April 1915 with the release by German Imperial troops of a massive chlorine cloud near Ypres, Belgium. The war became an accelerating competition between increasingly lethal agents and improvements in chemical defence. By late 1918 50% of all shells fired were chemical.
Spanish Morocco
Between 1921 and 1927 Spain and France deployed various chemical warfare agents against the Berber rebels during the Rif war. It was the first use of CW in a colonial war.
Italo-Abyssinian War
Italy resorted to CW (G) in its colonial campaign against Ethiopian troops between October 1935 and May 1936.
China
During the 2nd Sino-Japanese war (1937–45) Japan experimented with toxic chemical agents and used them extensively during the battle of Changde (November – December 1943)
Threat perceptions during the Interbellum
With the armistice chemical warfare ended.
Expectations were that if the war had continued into 1919 CW use would have surpassed that of conventional munitions. One new type of agent, Lewisite, was on board of transport ships en route from the USA to Europe when the arms fell silent.
The fear of CW did not disappear, however. World War 1 had been a war of innovation and aeroplanes in particular became part of future threat visions. Bombers armed with CW could annihilate whole cities, so it was feared. Politicians, peace campaigners, humanitarian organisations, etc., painted apocalyptic pictures of the end of humanity not unlike current views of nuclear warfare.
In Europe, a balance of terror combined with national civil defence preparations were among several factors that contributed to the prevention of gas warfare in World War 2.
Major CW Incidents After 1945
Viêt-Nam war
During the 1960s the USA progressively intensified the spraying of herbicides and defoliants over Viêt-Nam and neighbouring countries to deny North Viêt-Namese forces and insurgents jungle cover. Chemicals such as Agent Orange permanently destroyed large parts of the vegetation and are still the cause of illness and birth defects among the local population and US veterans.
Yemen civil war
Between 1962–70 several allegations were made that Egypt resorted to CW (G) during its intervention against Royalist forces. Some 40 incidents were reported.
Iran–Iraq war (1980–88)
Iraq initiated the largest CW use since World War 1 in 1982, possibly earlier. From late 1983 on CW became a regular feature and in the final two years systematised their use against Kurdish insurgents and civilians. Iran is not believed to have resorted to CW.
Syrian civil war
In 2013, two years into the war, reports of CW increased, culminating in the sarin attack against Ghouta in August. Since joining the CWC (G), attacks have continued with chlorine by both government forces and ISIL.
Cold War and its aftermath
World War 2 ended without sustained chemical warfare campaigns. The atomic bomb became the symbol of both military prowess and existential fear. CW disappeared to the background, but retained relevance for intra-war deterrence. The discovery of the extremely lethal and fast acting nerve agents in the 1930s drove post-war preparations. Up to end of the Cold War the USA and USSR built up and modernised arsenals comprising many tens of thousands of tonnes of warfare agents.
With the exception of the Viêt-Nam war, all major chemical warfare (G) occurred and is still occuring in the Middle East. It is a historical fact and psychological factor that has been mostly overlooked in the efforts to free the region from non-conventional weaponry.
In 1987 Iraq introduced CW as a means of genocide against the Kurds; a mode of warfare currently also being waged by Syria.
Terrorism with Chemical Weapons
How great a threat?
After the end of the Cold War concerns about catastrophic, mass-casualty terrorism rose fast. Aum Shinrikyo’s release of sarin in the Tokyo underground in March 1995 seemed to confirm the worst fears. After the 9/11 attacks against the USA, the fear escalated even further.
Until today the projected scenarios have not materialised. Acquisition of warfare agents have proved more complex than the availability of technologies and skills may suggest, not in the least because of the need for functional specialisation and the weapon programme alters internal group dynamics. Today greater transfer controls and law enforcement awareness have raised additional barriers.
Most incidents with toxicants are criminal in nature, including revenge attacks by individuals using commercial or off-the-shelf chemicals.
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Aum Shinrikyo’s high-tech apocalypticism
The Japanese cult developed an apocalyptic religious doctrine that required it to develop advanced weaponry to battle and survive the forces of evil. Its doctrine incorporated many science fiction elements, which was part of the group’s attraction for disaffected science and technology students and professionals.
Aum set up several weapon programmes, one of which was the production of 80 tonnes of sarin to help provoke Armageddon. It developed sarin and set up a production unit, which failed. However, the leadership became extremely paranoid about discovery as the project progressed. It also came in increasing conflict with Japanese society and the internal pressure to use the sarin to demonstrate its power before achieving full capacity grew. In June 1984 it created a sarin vapour to kill three judges set to rule in a land dispute; in March 1995 it released sarin in metro trains in Tokyo with the aim of preventing police raids on cult compounds. A far cry from its original goals, but the CW programme led to the cult’s demise.
ISIL’s opportunistic use of industrial toxicants
In 2006–07 al-Qaeda in Iraq launched a series of truck bomb attacks with chlorine against local Iraqi and US forces. The chlorine killed no one. AQI used the chlorine intended for water purification. AQI became the Islamic State in Iraq and the Levant (ISIL). In Syria it began experimenting with chlorine-filled mortar grenades, which in 2015 became more of a method of warfare rather than terrorism. It then expanded the practice in its operations against Kurds in Iraq. The OPCW (G) also confirmed incidents of ISIL mustard agent use in Syria and Iraq.