> I wonder if it's just an attempt to keep a cloud ...

Yes, but only peripherally. Atomic energy and atomic weapons are closely associated with a certain wealthy white western superpower. And within that superpower's political and ruling classes, there have been centuries of ideological struggles for what might be called "moral supremacy". Given how strongly the Hiroshima and Nagasaki A-bombing push many people's "Moral Issue" buttons - those naturally become a point of contention, with plenty of folks weighing in on them whenever it seems opportune to do so.