If the development by the enemy as well as by us of thermonuclear weapons could have been averted, I think we would be in a somewhat safer world today than we are...I do not think we want to argue technical questions here, and I do not think it is very meaningful for me to speculate as to how we would have responded had the technical picture at that time been more as it was later.

However, it is my judgement in these things that when you see something that is technically sweet, you go ahead and do it and you argue about what to do about it only after you have had your technical success. That is the way it was with the atomic bomb. I do not think anybody opposed making it; there were some debates about what to do with it after it was made. I cannot very well imagine if we had known in late 1949 what we got to know by early 1951 that the tone of our report would have been the same.

--Robert Oppenheimer testifying in his defense in his 1954 security hearings, discussing the American reaction to the first successful Russian test of an atomic bomb and the debate whether to develop the "super" hydrogen bombs with vastly higher explosive power; from volume II of the Oppenheimer hearing transcripts, pg 95/266