Physicist Edward Teller was instrumental in the United States' atomic weapons program, and along with his colleague Stanislaw M. Ulam, is credited with developing the world's first thermonuclear weapon, the hydrogen bomb. Prior to that he was part of the scientific team that developed the first atomic bomb at Los Alamos. Teller subsequently played a key role in establishing the Lawrence Livermore Laboratory -- the main U.S. thermonuclear weapons factory -- and in the Reagan administration's Strategic Defense Initiative. Teller was interviewed for COLD WAR in March 1996.

On the role of The Bomb in the Cold War:

The role of the atomic bomb was absolutely decisive. In 1945, the democracies demobilized; they had to. Public opinion would not support a big military effort in peacetime. Stalin did not demobilize. These facts were sufficient to establish a very probable victory of the Soviet Union in a conflict between very different views of the world. That was unavoidable. Because America could do better than anybody else in technical aspects, this period called the Cold War was in fact won by the United States. ...

In the United States, the money spent on nuclear explosives remained at all times well below 1 percent of the gross national product. In other words, in economic terms it had no effect. In the Soviet Union, with much less economic resources and with less expertise in the work on the atomic bomb, I have no doubt that their expenditure on atomic explosives was at least 10 percent of their gross national product -- and might have been very substantially more. I think that was a contributing factor. Do not underestimate, however, the simple psychological advantage. The United States, that never wanted war, had the advantage, an advantage [that was] passed into hands of people who wanted expansion, wanted worldwide domination more than they wanted peace. There, the substantial cost of this technical preparedness was more important.

On the H-bomb:

In the planning of that I was deeply involved, but I already had moved to a second laboratory [by then] and the older laboratory, Los Alamos, carried out that plan. I hoped very much that it would succeed. ...

As it turned out, its most important effect was not in the size of the explosion, although that counted. It was in the thoroughness of our knowledge of explosive release of nuclear energy. The effect was better ability to deliver explosives with as little expenditure as possible and giving effects by shock, by radioactivity, that we could influence more. We just had a weapon much better under control and let me try to make this very clear. In the first atomic bomb, we used elements like uranium, which were ready to burst, ready to undergo fission, release neutrons and use the same kind of nuclear disintegration in other nuclei and thereby created an explosion. In the hydrogen bomb, we used the lightest element, hydrogen, to release energy -- not by coming apart, but by getting together. It was a new principle, and it had to have and did have applications in making [and] in adapting nuclear explosives. ...

The most important thing about the hydrogen bomb was not that it could be made bigger and bigger. It was that it could be made more flexible. ... As accuracy increases, the importance of high explosives decreases. For reasons of military necessity, military advantage, the size of the atomic bombs remains limited. The availability, the cost ... could decrease -- and that was the main tactical effect of the hydrogen bomb.

On early nuclear testing:

They were more tests, Los Alamos tests, of the atomic bomb -- [the 1954 BRAVO test was] a little over-successful. The explosion was underestimated, was somewhat bigger. People were warned of radioactivity, but the direction of wind changed: islands in the Pacific got some of the radioactivity; quite a few people, including many natives, were exposed to radioactivity, but none got sick. And a Japanese fishing boat, I think the American translated name of it was "The Fortunate Dragon," got rained upon [by] the fallout [from a] couple of hundred miles away. We had instructed boats not to go there, [but] the Japanese disregarded it. Those people got quite sick, and one of them died of the effect of radiation. Now to my mind it is remarkable -- I won't say it's bad and I certainly won't say it's good, but I will say remarkable -- that this one death shocked Americans more than Hiroshima. It gave rise to enormous and unjustified fears of radioactivity. No, that fear was already there, but it seemed to justify that fear.

In the meantime, many studies ... collected data from Hiroshima, Nagasaki, Chernobyl, wherever there was a lot of radioactivity. We, of course, know that a lot of radioactivity is harmful, but what [is pointed] out is that we all are exposed to radioactivity and if the natural amount of radioactivity is multiplied by a factor 10 or more, the evidence does not show. The evidence seems to suggest that these low levels of radioactivity appear to be helpful rather than harmful. The fear of radioactivity has been greatly and improperly exaggerated and incidentally, interferes with reasonable plans to build more nuclear reactors for energy production.

On Manhattan Project physicist and Soviet spy Klaus Fuchs:

Klaus Fuchs: a very good scientist, a nice and gentle person, and a completely convinced communist, at least in the old days when I knew him -- although I did not know it at that time. Klaus Fuchs was very helpful to the Soviets in an early detonation of the atomic bomb. He was not, and could not have been helpful to the Russians in detonating [a] hydrogen bomb. I can say that now, after a number of discussions with Russian colleagues. We had in Los Alamos an approach to an atomic bomb that was imaginative and little risky and I think that Soviet scientists would never have taken the risk, had they not known about our work. You know, if they did not succeed, their life was on the line, every day. [They could] be sent into a concentration camp. They learned from Fuchs what we [had done] and therefore they not only dared think about it, but they had to do it.

On the Cold War:

I don't know whether the Cold War was necessary. I'm almost tempted to say that there never was a Cold War, there was no war. There was a confrontation; and that this confrontation did not lead to actual violence, that this confrontation could be resolved generally in favor of the ideas of democracy -- that was something perhaps without parallel in human history. If there was a Cold War, it was necessary. I'm not sure that there ever was one.

Here is the enormous difference between the first and second half of this century. ... The first half has seen two world wars: in the first more than 10 million people got killed; in the second, perhaps as many as 50 million. Conflicts on a comparably big scale in the second half did not occur. On the general historical record, the second half of the 20th century will go down as a peaceful period. And it was peaceful, because the power [was] in the hands of those who wanted peace.

On the political role of scientists:

I think we scientists have the job to make knowledge available in greater and greater and unlimited amounts. It is not our responsibility to determine what to do with this knowledge. That, in a democracy ... is the job of the people -- a job that in many respects can be and has to be delegated, but not to the scientists, [but] to the people chosen [in elections] -- and I should say somehow, with God's help, rightly chosen.

The dangers of the world in my mind [are] not knowledge. The dangers of the world are mostly summarized in one word: stupidity. ... We will be forever in need of leaders ... who [have] an unequally small share of the general human stupidity, who are a little better in judging the future and finding the best for everybody and therefore also for themselves. That is the general need. And our special need is knowledge, knowledge and more knowledge, which we can place ... into the hands of people who are perhaps a little less stupid than the rest of us.