Congolese Uranium, Nazi Germany and the Race to Build the A-Bomb

Congo miner looks for cobalt
A man digs through mine waste in search for cobalt between Lubumbashi and Kolwezi in Democratic Republic of Congo, May 31, 2015. Congo's rich mineral deposits, including uranium, have long attracted foreign companies and stakeholders. FEDERICO SCOPPA/AFP/Getty Images

In 1939, Albert Einstein signed a letter to President Franklin D. Roosevelt warning of the potential of the Nazi regime to develop an atomic bomb. He urged him in particular to protect the uranium from the Shinkolobwe mine in the Belgian Congo—what is now Democratic Republic of Congo—which was the richest in the world: an average of 65 per cent uranium oxide, in comparison with American or Canadian ore, which contained less than 1 per cent. After Adolf Hitler's surrender in May 1945, Einstein regretted signing the letter and called on President Harry Truman to halt the atomic project. But his warning to Roosevelt had fired a starting-pistol in the race to secure the ore. General Leslie R. Groves, director of the secretive Manhattan Project, sought to obtain all the Congolese uranium for America and to prevent any of it from reaching Germany.

General Groves adopted a worst-case scenario: that unless and until it was confirmed otherwise, they should assume that Germany was working on a bomb at full capacity. This position was shared by President Roosevelt and Winston Churchill, who had agreed that Britain should cooperate with the U.S. on the construction of the bomb; British scientists working on Britain's secret atomic bomb project—Tube Alloys—were sent to the U.S. to join the Manhattan Project.

When Roosevelt met Churchill for talks on June 19, 1942 in Hyde Park, New York—where the atom bomb was "the most complex and, as it proved, overwhelmingly most important subject" on the agenda—they speculated on German progress. "We both," wrote Churchill in his memoirs, "felt painfully the dangers of doing nothing. We knew what efforts the Germans were making to procure supplies of 'heavy water'—a sinister term, eerie, unnatural, which began to creep into our secret papers." What, he exclaimed in horror,

If the enemy should get an atomic bomb before we did! However sceptical one might feel about the assertions of scientists, much disputed among themselves and expressed in jargon incomprehensible to laymen, we could not run the moral risk of being outstripped in this awful sphere.

In the summer of 1943, Roosevelt told James Byrnes, then Director of the Office of War Mobilization, about the Manhattan Project, asserting that the Germans were ahead of the U.S. in the atomic race. The President's belief, wrote Byrnes years later, stimulated the "extraordinary efforts put forth on the Manhattan Project," which at its peak claimed the labour of 125,000 men.

The safeguarding of information was secured by a strict 'need to know' policy: not one of the laboratories, universities, plants or contractors was given any information about the overall structure of the Project. "The majority of workers did not know what the Project was doing, or what other plants at their own site were doing, or what the other departments in their own plant were doing," records an institutional history of the Counter-Intelligence Corps (CIC), an intelligence organisation within the American military that was given responsibility for the Project's security. "All the sites, materials and special items of equipment were given code names. So were many of the scientists. And since the top scientists were the few people who did know what the Project was about, they were given bodyguards from a special group of CIC agents—who were really spying on them."

"Only about six men in the U.S. Army," commented the physicist Arthur Compton, a Nobel Prize winner who was involved in the Manhattan Project, "are permitted to know what is going on, including Secretary of War Stimson!" Byrnes described the resounding silence on the topic in the corridors of power:

After the first discussion, neither the President nor I mentioned the atomic project to each other for many months. In fact, no one ever talked about it unless it was absolutely necessary. I remember once mentioning it to Secretary of War Stimson who, from its very inception, personally supervised the Manhattan Project. His reaction indicated surprise that I knew about it.

Even by April 1945, adds Byrnes, only four members of Congress had been given any concrete information about the Project. Harry Truman was not informed of the Project before assuming the presidency after Roosevelt's death in April 1945.

This secrecy extended firmly to everything related to Congolese uranium and the Shinkolobwe mine. The Belgian uranium deals were "one of the most tightly kept secrets" of the war, notes Jonathan Helmreich in a detailed study of America's relations with Belgium and the Congo between 1940 and 1960. "The most important deposit of uranium yet discovered in the world," stated a top secret American intelligence report in November 1943, "is in the Shinkolobwe Mine in the Belgian Congo." The Congo's "known resources of uranium, which are the world's largest," added the report, "are vital to the welfare of the United States...Definite steps should be taken to insure access to the resources for the United States."

It was a matter of great urgency to the U.S. to persuade Union Minière du Haut Katanga, the huge Belgian company which owned the Shinkolobwe mine, to reopen it as soon as possible, in order to acquire all its uranium ore. Negotiations were held with Union Minière, Belgium and Britain; meanwhile, careful plans were drawn up regarding logistics, methods and costs.

The only major deposit under Nazi Germany's control was at Joachimsthal, in Czechoslovakia. But the production of the Joachimsthal deposits was small, when compared to that of the Belgian Congo, or even to that of Canada and the United States.

Groves was assured by his intelligence and security aides that Germany was not getting any uranium from the Congo. "There is no evidence," he was told, "that any concentrates or ores are reaching destinations other than the U.S."

But Groves was not willing to take any chances—he was determined at all costs to stop Hitler's forces from obtaining Congolese uranium ore. It was possible, though difficult, to try to ensure that Germany did not obtain the ore through legitimate channels. Much more challenging was the threat of smuggling: there were already well established smuggling routes from the Belgian Congo to Germany, which could be used to transport the ore.

To deal with this threat, Groves turned to the Office of Strategic Services, a wartime intelligence service which had been newly set up by Roosevelt. In late 1943, OSS sent a top agent to Africa to tackle the problem of smuggling: Wilbur Owings 'Dock' Hogue, a sombre and very clever civil engineer, who became OSS chief of station in the Belgian Congo. He was joined in 1944 by Henry Stehli, a sophisticated but easygoing man who worked in peacetime in the family business—the famous Stehli Silks Corporation. The OSS station office in Léopoldville was managed by Shirley Chidsey, a petite woman whose size belied her adventurous spirit and lively nature.

Dock Hogue in Belgian Congo
A screenshot from a home movie shows Dock Hogue, an OSS agent, at the U.S. Consulate General in Léopoldville, Belgian Congo, 1944. Hogue was part of a U.S. team working to stop Nazi Germany accessing Congo's rich uranium mines. Hogue Film, Hogue Family Papers

Other OSS agents stationed in West Africa also participated in the mission in significant and covert ways. From Washington, this network of agents was directed by the Africa Section of OSS Secret Intelligence; its chief was Rudyerd Boulton, an ornithologist in peacetime, whose commitment to his new post led him at times to be tough, even ruthless. His task was made all the more difficult by the obstacles in the field, such as poor channels of communication, erratic means of travel, lack of adequate information, and frequent severe illness.

For over seventy years, this mission has been unknown to the world, and not one of those who carried it out has received recognition. Their service was concealed by the total secrecy that blanketed everything to do with the Manhattan Project—and especially its reliance on the uranium ore from the Shinkolobwe mine in the Congo.

This piece is an edited extract from Susan Williams's book Spies in the Congo: The Race for the Ore that Built the Atomic Bomb. The book is published by Hurst in the U.K. and PublicAffairs in the U.S.