alternatehistory.com

With a PoD during or after the Trinity nuclear test in 1945, have the Acheson-Lilienthal plan - or some approximation of it - succeed. The key metric of success is whether any nation or other entity is stockpiling nuclear weapons or weapons material.

For those unfamiliar with the plan: after WW2, there was a very brief window - finally closing completely with the Berlin Crisis - where it seemed that international control of atomic energy and the elimination of atomic weapons might actually be achieved through the UN. The effort foundered on mutual distrust, the USSR's demand that the US give up its bombs before negotiating an inspection agreement, and the US's demand that the USSR negotiate an inspection agreement before we would give up our bombs.
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