Canada and Weapons of Mass Destruction | The Canadian Encyclopedia


Canada and Weapons of Mass Destruction

Canada has a long, complicated history with weapons of mass destruction (WMDs). Canadian soldiers have been attacked with chemical weapons and have used them offensively. (See Canada and Gas Warfare.) Canada has researched chemical, biological and nuclear weapons; but also, ways to defend against them. Some chemical weapons were tested in Canada and against Canadians with long-term consequences. Canada played a crucial role in the development of nuclear weapons. (See Canada and the Manhattan Project.) The country employed nuclear weapons primarily as defensive weapons during the Cold War. Canada signed international documents limiting the use of these weapons. Canada no longer has weapons of mass destruction. However, Canada is a member of the North Atlantic Treaty Organization and NORAD — alliances that employ nuclear weapons and other weapons of mass destruction.

RCAF CF-101 Voodoo alongside a Genie air rocket which could be armed with a nuclear warhead


Weapon of mass destruction: Any weapon capable of causing extremely high casualties and/or massive destruction. These are typically chemical, biological, radiological or nuclear in nature. The initialism CBRN is used to specify these types of weapons.

Chemical weapon: A weapon that uses chemicals to kill or maim, typically spread as a poisonous gas. Chemical weapons were used extensively in the First World War.

Biological weapon: A weapon that uses infectious agents like viruses, bacteria or biological toxins to kill or maim. The deliberate use of a disease in warfare would be an example of biological warfare.

Radiological weapon: A weapon designed specifically to kill using radiation poisoning. It can also cause radiological contamination over a large area.

Nuclear weapon: A weapon that creates a massive explosion from a nuclear reaction — either fission or a combination of fission and fusion reactions. Nuclear weapons create massive and powerful shockwaves as well as giant fireballs. They also cause radiological contamination, which typically results in higher cancer rates and death.

Colonial Era

British general Jeffery Amherst proposed using a form of biological weapon during Pontiac’s Rebellion in 1763. (See Obwandiyag.) Amherst suggested sending blankets infected with smallpox to the Indigenous warriors besieging Fort Pitt (modern-day Pittsburgh). It was known that Indigenous people were more susceptible to infection and death than Europeans. (See Disease.) In fact, a trader at the fort had had the same idea. He gave infected blankets from the fort’s hospital to two Indigenous emissaries.

Amherst wanted to eliminate Indigenous people altogether — what we today call ethnic cleansing or genocide. (See Genocide and Indigenous Peoples in Canada.) It isn’t clear if his plan succeeded, but it is clear what Amherst’s intent was. Amherst was for many years considered a hero in Canada because of his successful Conquest of New France. Today, his legacy is being re-evaluated.

First World War

Chemical weapons were employed by all the main belligerents in the First World War, including Canada. (See Canada and Gas Warfare.) Germany used chlorine gas for the first time during the Second Battle of Ypres against French and Algerian troops, but also Canadian soldiers. (See Canadian Expeditionary Force.) The first chemical weapons had to be handled by specialist soldiers and required strong winds to be blown across the battlefield. Eventually, new systems were developed to deploy the gas like artillery shells and gas projectors. Chlorine gas had a peculiar colour and a distinct odour; however, newly developed gases were odourless and colourless. This made detection more difficult. To counter toxic gases, gas masks and other defensive tools were developed to counter the threat.

Gas projectors used by Canadians during the advance on Lens, September, 1917.

By the end of the First World War, the use of poison gas had become routine. Soldiers regularly went into battle wearing their gas masks. Gas masks had even been developed for horses. Canadian soldiers deployed gas during the Hundred Days Campaign towards the end of the war.

Second World War

Leading up to the Second World War, countries feared that chemical weapons would be widely used. Prior to the war, Italy used lethal gas against Abyssinia (Ethiopia). Japan also used chemical and biological weapons during its invasion of China from 1937 onward. Both Abyssinia and China did not have chemical weapons to fight back. This likely encouraged Italy and Japan to use poison gas.

Chemical weapons were not used against countries that also had such weapons. None of the Axis or Allied powers with poison gas used it against each other. The fear of their use, however, led both sides to produce chemical weapons and protective equipment.

Canada signed the Geneva Protocols of 1925, which was intended to stop the use of chemical weapons. Nonetheless, Canada was actively involved in chemical and biological weapons research and production. The Suffield Experimental Station in Alberta was jointly funded by Canada and Britain. (See Canada and Gas Warfare.) 

Canadian scientists were involved in developing biological weapons, namely anthrax. Canada’s bio-weapons program was located at Grosse Île near Quebec City. (See also Grosse île and the Irish Memorial National Historic Site.) The facility was shut down at the end of the war. However, Canada continued developing biological weapons during the Cold War. These tests were mainly done at the Suffield facility.

Canada contributed to the development of the most destructive weapon ever created — nuclear weapons. Much of the British research on nuclear weapons was transferred to Canada in 1942. The British-Canadian research then merged with the American effort, called the Manhattan Project. (See Canada and the Manhattan Project.) The objective was to turn this research into a functional nuclear weapon. Uranium mined by the Dene people of Délįnę, Northwest Territories, may have been used for this; however, this hasn’t been conclusively proven. Nevertheless, Canada would supply uranium to the US nuclear program from 1945 until at least the 1960s. Canada’s participation in the Manhattan Project eventually led to the creation of Canada’s nuclear energy industry.

Photograph of the Eldorado Mine

Cold War

Canada operated several different types of nuclear weapons during the Cold War, from about 1964 through 1984. Some were deployed with Canadian Forces in Western Europe. These were intended to be used against the military forces of the Warsaw Pact in case of attack. Other nuclear weapons were used in Canada to defend against Soviet planes and missiles. Canada had nuclear-tipped rockets, surface-to-air missiles with nuclear warheads, nuclear bombs carried by jet fighters and artillery rockets with nuclear warheads. (See also Bomarc Missile Crisis.)

Bomarc Missile

The United States deployed long-range bombers and about a dozen nuclear bombs in Canada These were stationed at an air base in Labrador for a brief period in the early 1950s. Nuclear depth charges were also issued to a naval base in Newfoundland up until the early 1970s.

Canada operated its nuclear weapons under a “dual key” arrangement. Canada’s nuclear weapons were to be used only with joint authorization with the United States. They were only to be used in case of a full-scale nuclear war. This arrangement was common among the nations of the North Atlantic Treaty Organization (NATO) during the Cold War.

Canada worked with the United States to protect North America from nuclear attack. Together, they created NORAD and developed long-range early warning radars. Radar stations and signals intelligence stations were installed in the High Arctic. These allowed Canada and the United States to detect Soviet aircraft or missile launches with enough advance warning to theoretically counter them.


Prime Minister Pierre Elliott Trudeau was outspoken in his opposition to nuclear weapons. Canada signed the Treaty on the Non-Proliferation of Nuclear Weapons in 1968. Canada phased out its nuclear weapons between 1968 and 1984. (See Disarmament.)

Canada ratified the Biological Weapons Convention in 1972, and the Chemical Weapons Convention in 1995. Since 1990, the Biological and Chemical Defence Review Committee has been supervising the disposal of chemical and biological weapons tested on Canadian soil. It is not believed that Canada possesses any weapons of mass destruction. It does, however, maintain the ability to defend against them. Moreover, Canada is still protected by the American nuclear umbrella. Canada is also allied to other nuclear powers through NATO.

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