>an entirely American project until the technology was exfiltrated
replyNo it wasn't. https://en.wikipedia.org/wiki/Tube_Alloys
Post WW2 the USA (for a bunch of quite interesting reasons) excluded the British. But, of course, the British had acquired a lot of knowledge from the program and were able to develop their own bomb.
There were prominent scientists like Oppenheimer who did not think it needed to become an arms race, and campaigned against that. But there were others like Teller and the military who made it into an arms race, and kept upping the ante with more powerful nukes.
replyPoint being humans make theses decisions. It's not an inevitability.
It was an inevitability. Unfortunately Oppenheimer was a fool when it came to politics. In game theory terms, the perceived benefits of "defecting" were too large.
replyThe military mostly only developed more powerful nukes because early delivery and guidance systems were so inaccurate that they needed a large blast radius to hit anything. Once enabling technologies improved, R&D shifted from power to accuracy.