It was immediately made a crime punishable by death in both the US and Japan to discuss nuclear attacks and the technology that created them. (“The restricted dataclauses of the US Atomic Energy Act specifies that all nuclear weapons-related information is to be considered classified unless explicitly declassified, and makes no distinction about whether said information was created in a laboratory by a government scientist or anywhere else in the world by private citizens.”)Nope. A couple months ago I was looking through a 1945 publication to find tube-type electronics ideas, and noticed that the October issue of this journal included a full tutorial for making an A-bomb. Clearly the official attitude in late 1945 was open-sourcey in modern terms. The military wanted to help create a balance of power. See p. 113 of the PDF.
The current icon shows Polistra using a Personal Equation Machine.