Why would President Truman be against sharing the secret of the atomic bomb with the world? Why would he support sharing atomic technology with Great Britain and only give minor details to the Soviets, who were also allies?

He wanted to seem like the U. S. had a bigger and better weapon than the rest of the world did so they would not be hostile to us. he supported giving it to Britain and the Soviet union because they supported us and allied with us in the war

Explanation:

common sense

He didn't want to share the information because no one else had this massive weapon and it was the first of its kind to be made. And most of the info got leaked to the Soviets and Britains by scientists who worked on the bomb, fearing that the US might be too strong with this power.