A little more than 100 years ago, at the Second Battle of Ypres, the German Army unleashed the first large scale use of poison gas on the Western Front. Following a two-day bombardment, the German Army simultaneously released 168 tons of chlorine gas over a four-mile front.
The panic that resulted opened a four-mile gap in the Allied lines. The First Canadian Division, stationed at St. Julien, was on the flank of the gap. In what was considered a suicide mission, they were ordered to counterattack and prevent the Germans from advancing through the opening.
Lacking gas masks, they improvised by urinating on cloths and holding them to their faces. The ammonia in the urine neutralized the chlorine gas. The Canadians’ victory that day marked a second milestone – it was the first time that new world soldiers had won a victory on a European battlefield.
For all of its deadly effects, chlorine had shortcomings as a weapon of mass destruction (WMD). It was easily dispersed by the wind, limiting its effects. To compensate, the Germans developed sulfur mustard, otherwise known as mustard gas, which they used at the Third Battle of Ypres in July 1917.
The gas had a yellow color and smelled of mustard plants and garlic, hence its name. Mustard gas was heavier than chlorine gas, less likely to be dispersed by wind and its effects on the battlefield persisted longer.
When the Second World War broke out, both sides stockpiled poison gas. The Italians used mustard gas during the Abyssinian campaign in 1935; the Polish Army used mustard gas grenades during the Nazi invasion in 1939. The Japanese reportedly used poison gas in Manchuria.
Winston Churchill authorized the use of gas against German troops if they invaded Great Britain and considered using mustard gas bombs against German cities. Adolf Hitler contemplated using gas during the siege of Leningrad, but also opted not to go through with it.
Since the Second Word War there have been sporadic uses of poison gas. Egypt used poison gas, possibly mustard gas, during the civil war in North Yemen between 1963 and 1967. Vietnam used phosgene, another First World War-era poison gas, against Cambodian forces during the 1984-85 Cambodian intervention that toppled Pol Pot. Both South African troops and Cuban troops were accused of using chemical weapons during the Angolan Civil War.
Saddam Hussein used chemical weapons, including mustard gas, against Iranian forces during the Iraq-Iran war. He also used them against Kurdish civilians in northern Iraq and against Shiite rebels in the Shat al-Arab marshes.
Syrian military forces have used chemical weapons against various Syrian rebel groups and civilians. In August 2012, U.S. President Barack Obama warned Syrian President Bashar al-Assad that the use of chemical weapons by his forces would represent a red line for the U.S. Unfortunately, the threat proved to be hollow.
In September 2013, Russia brokered an agreement for Syria to turn over its chemical weapons for destruction under UN supervision. These amounted to around 1,000 tons of sarin, mustard gas and VX.
Chlorine, the original First World War-era poison gas, was exempted since chlorine gas has widespread use in industry. Virtually every municipal waterworks uses liquid chlorine to disinfect water supplies.
Despite the agreement, however, there have been widespread reports that the Assad government has used chlorine gas in the barrel bombs that it uses to target civilians. There have also been unverified reports that the Assad government retained some stocks of sarin and VX gas.
Poison gasses, not surprisingly, are popular among terrorist organizations. They are the cheapest WMDs and the easiest to produce. The Japanese group Aum Shinrikyo used sarin gas in an attack in Matsumoto, Japan, on June 27, 1994. The following year, they released sarin gas into the Tokyo subway system.
Various jihadist groups have exploded tankers of chlorine gas as improvised WMDs. According to Pentagon sources, Islamic State (IS) has also been producing mustard gas since 2015.
Kurdish and other sources claim that Islamic State has fired artillery shells and mortar rounds containing mustard gas; however, follow-up tests have proven inconclusive. Nonetheless, Sleiman Daoud al-Atari, the recently captured head of Islamic State’s chemical weapons program, has admitted to U.S. interrogators that IS has amassed a stockpile of mustard gas, which it intends to deploy in the upcoming battle of Mosul.
Mosul’s fate can only be devastatingly tragic by Joseph Micallef
On Sept 12, 2016, U.S. warplanes destroyed a pharmaceutical factory in Mosul that U.S. Central Command believes had been converted into a chemical weapons manufacturing facility.
Mustard gas can be used both as an offensive weapon against advancing troops and, in large quantities, to create area denial zones that prevent the advance of Iraqi troops and force them into preselected attack routes set up as kill zones.
In anticipation of a mustard gas attack, the U.S. has distributed some 50,000 kits of “personal protective gear” to Iraqi and Kurdish forces. The Shiite militias, interestingly enough, do not have protective gear, a factor that may limit their involvement in the Battle of Mosul. Iran, however, could supply such gear.
After an absence of almost a century, mustard gas is about to return to the modern battlefield.
Joseph Micallef is a historian, best-selling author and commentator on world politics.