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Updated: Aug 7, 2023

Canada played a key role in the atomic bombing of Hiroshima and Nagasaki, but few Canadians are aware of it. In August 1943 Canadian Prime Minister Mackenzie King invited US President Roosevelt and British Prime Minister Winston Churchill to a conference in Quebec City. When the two leaders signed the Quebec Agreement for joint development of the atom bomb, the agreement made Canada also a party.

Mackenzie King appointed Minister of Munitions and Supply C.D. Howe to serve on the project’s Combined Policy Committee. The National Research Council of Canada’s president was made a member of a technical committee to coordinate American colleagues with scientists working on Canadian projects. The NRC had been researching atomic fission at a Montreal laboratory established in 1942 to absorb scientists and work of a British project named Tube Alloys. Some dozen researchers from six Canadian universities participated in the Manhattan project.

Canadian company Eldorado Gold Mines had a uranium mine on Great Bear Lake in the North West Territories.  it had begun to supply uranium ore to British and American scientists investigating nuclear fission at Columbia University in New York in October 1939, and also provided uranium ore to Enrico Fermi, who created the first self sustaining nuclear chain reaction in December 1942, at the University of Chicago.

Eldorado — now Eldorado Mining and Refining — contracted with the Manhattan Project in 1943 to supply 850 tons of uranium ore. Dene hunters and trappers from Deline were hired to carry hundred pound sacks of uranium concentrate on their backs from the company’s Great Bear Lake mine at Port Radium to barges.  The ore was transported 3,400 kilometres by rivers, rapids, and portages, to Fort McMurray, Alberta, and then by train to Port Hope, Ontario. The Indigenous carriers didn’t know of the radium in the uranium ore. The Canadian government had long known about the danger of radiation poisoning from radium, but the Dene were never warned. Their community was also left with 1.7 million tons of uranium waste dumped into Great Bear Lake.

In mid July 1943 the Canadian government secretly bought enough shares in Eldorado to control the company, and the following January nationalized it to secure uranium for the Manhattan Project. The Port Hope refinery was the only one capable of refining the Canadian ore and the other major source of uranium ore, which came to Canada from the Belgian Congo. The bulk of the Belgian ore, along with Canadian uranium, was used to manufacture the atomic bombs. The NRC’s Montreal Lab designed and built some of the world’s first nuclear reactors as part of the Manhattan Project. The US supplied instruments, drawings, information, and experienced US scientists’ advisory services.  The lab provided essential data for design of a fission reactor, and for chemical plants to extract uranium 233 and plutonium required for the hoped for weapons. Plutonium was an element in the bomb dropped on Nagasaki. Atomic fission labs were operating at the Montreal Lab from 1942. Canada had a supply of heavy water and the Combined Policy Committee, with Howe and Mackenzie in attendance, decided in April 1944 to design and construct a heavy water moderated nuclear reactor in Canada, largely to pro0vide information about the efficiency of such a reactor to the US. The National Research Experimental reactor – NRX – was built at Chalk River and opened in 1944 though it didn’t achieve fission until July 1947.

Churchill and Roosevelt believed in bombing cities as a key method of war. In March 1945 the US began firebombing Japanese cities, targeting all but seven.  How the atomic bombs would be used worried a small group of Manhattan Project scientists. In June they wrote the Franck Report, which proposed they be dropped in AN uninhabited location to demonstrate their extreme power, and they forwarded it to the small committee under US General Leslie Groves charged with making the decision.  Already in 1944 the Japanese were seeking to surrender, engaging American diplomats.  Groves wanted a military target where there were civilians, in order to test the effects of the atomic bomb.  Mackenzie King’s diary shows he knew the atomic bombs would be dropped on Japan. The frantic effort to produce them had begun when it was feared Nazi Germany was developing them.

As a then 15 year-old Canadian, I was horrified at the utter cruelty of the bombings. Canadians need to know that Mackenzie King noted “It is fortunate that the bomb was used upon the Japanese rather than on the white races of Europe.”

When World War II ended in August 1945, the world was split: the “west” and the Soviet Union. In September Canada learned through Soviet embassy clerk Igor Gouzenko that a Russian spy network had acquired classified nuclear information in Canada.  Canada joined the US and the UK in forming the nuclear-armed North Atlantic Treaty Alliance (NATO) in April 1949. The Soviet Union exploded its first atomic bomb in August 1949. To counter Soviet aviation sorties, Canada and the US constructed radar networks across the north, and they formed NORAD, the North American Air Defence Command, in May 1958. Canada continued supplying uranium and plutonium to the US and the UK for two decades. Then it became a salesman of nuclear power, to Pakistan, dictator-ruled Argentina, and apartheid South Africa. By its sale of a CIRUS reactor to India, Canada enabled India to develop and explode its first atomic bomb in 1974. Canada had nuclear-armed Bomarc missiles on Canadian soil from 1963 to 1971, and from 1983 through the 1990s allowed testing of cruise missiles that would be nuclear armed. Until the end of the 1970s Canadian interceptor aircraft were armed with nuclear genie rockets.

Canada remains committed to nuclear deterrence, allegedly, for Canadian security. It paid little attention as, over the years, nuclear arsenals were expanded and doctrines changed: nuclear missiles for battlefield use, first strike policy being added to deterrence, and now more usable low yield weapons and proposals that they be employed to gain victory in a conventional war. Canada participates in NATO’s nuclear policy planning group. Only once, in a December 1998 speech by Foreign Minister Lloyd Axworthy, did Canada raise at NATO the need to examine its nuclear strategy, noting 93% of Canadians expect Canada and its Allies to take the lead in working to eliminate nuclear weapons. Earlier, at the UN Special Session on Disarmament in 1978, Prime Minister Pierre Trudeau HAD GIVEN hope in a speech on a strategy of suffocation of nuclear weapons to halt and eventually reverse the nuclear arms race, but the super powers were indifferent.

Canadians held peace protests from the 1950s. In 1961 Canadian Voice of Women for Peace (VOW) was founded, in 1976 Project Ploughshares, then Science for Peace, Peace Brigades International, Veterans Against Nuclear Arms (VANA), physicians and lawyers anti–nuclear associations, and in 1996, CNANW — the Canadian Network to Abolish Nuclear Weapons. Cities voted to be nuclear weapons free zones – Toronto in 1982. Citizens protested Litton Industries’ production of cruise missile parts that year.  Churches took a stand against nuclear weapons. Peace activists joined Labrador Innu in protesting NATO fighter-bomber low-level training from Goose Bay over the Innu’s inhabited, unceded territory. VOW and Science for Peace began calling for Canada to get out of NATO. Canadian peace activists worked with international lawyers’ and physicians’ NGOs in the World Court Project, obtaining an advisory opinion in 1996 that use of nuclear weapons would In general be illegal in light of international humanitarian law. Ploughshares joined ICAN, the International Campaign to Abolish Nuclear Weapons in 2007. CNANW and its member groups are urging Canada to join the resulting 2017 Treaty on the Prohibition of Nuclear Weapons, as are seven cities, including Toronto, Oakville, and Cape Breton.  In a December 2018 letter all 26 denominations of the Canadian Council of Churches urged the Trudeau government to support the treaty and to raise the issue of nuclear weapons with NATO.  Canada must heed its citizens!

  1. the recorded speech, delivered on 6 August 2020, can be found on the website of the Hiroshima Nagasaki Day Coalition (


Phyllis Creighton,  longtime SfP board member and now honorary life member, is an ethicist, historian, writer, and retired editor.

Image by WikiImages from Pixabay


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