I WANTED TO ASK YOU A COUPLE OF GENERAL QUESTIONS FIRST, AND THEN TALK ABOUT MORE SPECIFIC THINGS ALONG THE CHRONOLOGY OF OUR TIME PERIOD. EARLIER YOU WERE TALKING SOMEWHAT ABOUT THE IDEA OF THE TECHNOLOGICAL IMPERATIVE. DO YOU FEEL THAT THE DEVELOPMENT OF THE ATOMIC BOMB WAS INEVITABLE?

Yes, I think the development of the atomic bomb was, was inevitable. And I think the main reason for that was that the principle, namely nuclear fission, was known to both sides of the great Second World War. The Second World War was a desperate war. It would have been absolutely awful if Hitler's Germany could have won that war.

SO YOU THINK THE FACT THAT ATOMIC PHYSICS HAD PROGRESSED TO THE STATE IT WAS AT IN THE LATE '30S, COUPLED WITH HITLER IN GERMANY LED, INEVITABLY TO THE DEVELOPMENT OF THE BOMB?

Ah, yes. I think that is so. The nuclear physics, in particular the response of atomic nuclei to neutrons had been investigated since 1935, mostly by the Italian school under Fermi. They had found very peculiar results in the case of uranium. And then these results were further investigated and clarified by Hahn and Strassmann in Germany, who found that the nucleus of uranium does something entirely different from other nuclei. Namely, instead of adding a neutron to it, it splits when it's bombarded by a neutron.

DURING THE WAR YEARS, AND UP THROUGH 1946, DURING THAT PERIOD, DO YOU SEE ANY EVENTS AS HAVING BEEN REALLY TRAGIC IN TERMS OF THE LOST OPPORTUNITY TO PUT SOME CONTROLS ON ATOMIC WEAPONS?

Well, you could think of two. The ah...no I would say three, lost opportunities. The most important one was the one that Niels Bohr proposed repeatedly to President Roosevelt and Prime Minister Churchill. Namely, to let the Russians know that we were pursuing atomic, the idea of atomic weapons, without telling them any technical details...

I'M GOING TO STOP YOU FOR A SECOND. COULD YOU START AGAIN, AND USE THE WORD 'LOST OPPORTUNITY'? COULD YOU SAY, 'ONE SIGNIFICANT LOST OPPORTUNITY WAS...'

OK. The most important lost opportunity was that the statesmen did not follow the suggestions by Niels Bohr. Namely, to tell the Soviets, who were then our allies that we were engaged in making an atomic bomb. This was surely regarded by the Russians as a sign of lack of confidence. Of course, they didn't have any confidence in us either, but I think it was up to the western allies to take the initiative in this matter. And this might have changed quite a great deal. The, as a matter of fact, it later turned out that the Soviets already started in 1943 on work leading ultimately to the design and manufacturing of an atomic weapon and they were certainly very much helped by the treason of Klaus Fuchs, which also we did not know about. Well, that was one lost opportunity. Another lost opportunity was that we dropped two bombs on Japan. I think it was necessary to drop one, but the second, I think, was, could easily have been avoided. I think Japan would have capitulated anyway. But, by that time, the decision of using the second bomb was left to the field commander and field commanders use whatever they have. The third opportunity, which some people now quote is that we might have stopped pursuing the atomic project after the defeat of Germany. I don't think that would have been possible. There was so much momentum by that time in the American development that it would have been very difficult to stop and General Groves, who led the project was always deadly afraid of the subsequent congressional investigation. And the congressional investigation in that case, could have been very detrimental to the General as well as perhaps to us. Anyway, nobody at that time in May of 1945, was even thinking of stopping. Except one person, a Pole on the British missile mission.

YOU'RE THINKING OF ROTBLAT, JOSEPH ROTBLAT. WE'RE GOING TO SEE HIM IN ENGLAND...

I see.

SO JUST TO PICK UP ON ONE THING YOU SAID, IS IT A GENERAL PRINCIPLE OF SCIENTIFIC AND TECHNICAL PURSUITS THAT ONCE SOMETHING GETS ROLLING IT'S HARD TO STOP?

It is certainly a principle of scientific, technical pursuits that once something gets rolling it is very hard to stop. Now, I think you should distinguish between scientific endeavor and technical developments. In scientific endeavor, one is just driven by the urge to know. And as long as something is partly understood, we want to understand all of it. In technical pursuits, like the atomic weapon, it is very largely the number of people involved, the hardware involved, the institutional backing and I may use a present example, namely the Strategic Defense Initiative, which I believe is a totally fad concept, but it will be very hard to stop as soon as a lot of industrial work is involved in it. Industrial companies need work. And so once they are engaged in it, they will continue. And will very strongly argue for continuation --

YOU USED THE PHRASE EARLIER OF THE TECHNOLOGICAL IMPERATIVE, YOU USED IT IN YOUR WRITINGS. COULD YOU JUST GIVE US A DEFINITION OF THAT?

Definitions are hard to give, but examples are easier to give. The, well, there are many people in this country who think that when something is technically possible, it has to be pursued. And particularly so if it is of a military nature, which might give us a relative advantage, relative to our competitors. One of the prime examples which I like to quote is the MIRV. The Multiple Independently-Targeted Reentry Vehicle on a ballistic missile. This was an invention in the United States. We had made some technical advances in this and so we insisted in pursuing it, even though many people at that time, which meant around 1970, knew perfectly well that this was an invention which in the end would benefit the Soviets because they have much bigger missiles on which they can carry many more warheads than we can.

WELL WAS THERE ANY SIGNIFICANCE IN THE IDEA OF TECHNOLOGICAL IMPERATIVE DURING WORLD WAR II, DURING THE DEVELOPMENT OF THE BOMB?

I don't believe that anybody was conscious that this was a technological imperative. I think that we were searching and I think this goes very broadly, the United States technicians were searching for various ways to defeat Germany and Japan. And probably the most important was radar. And I don't believe that, that people said, here is the concept of radar. It might be some good, might give us some advantage. But instead they said, we need desperately some way to counter the German superiority in war planes. What can we do? So I think this is a different argument than the technological imperative.

GOING BACK TO THE DAYS BEFORE THE WAR, YOU WERE TELLING ME EARLIER BEFORE WE STARTED SHOOTING, COULD YOU TELL ME AGAIN HOW YOU HAPPENED TO COME TO THE UNITED STATES AND WHEN?

I came to the United States in February of 1935. I had emigrated from Germany earlier. I think September of 1933. And the reason was that my mother was Jewish and according to the Nazi laws, the child of one Jewish parent could not hold any official position in any federal or state government, or German universities run by the state. And therefore it meant that I could not hold any university position. But I wanted to be a scientist, so I had to have a university position. So I emigrated. There was no immediate danger for me of life and limb, but there was danger to my career. In fact, it was clear that I couldn't have a career.

SO YOU WERE IN THE UNITED STATES. WERE YOU AT BERKELEY WITH OPPENHEIMER WHEN THE NEWS OF THE HAHN/STRASSMANN EXPERIMENTS CAME?

No, I was at Cornell from the day that I landed in the United States.

I WANTED TO ASK YOU A SLIGHTLY DIFFERENT QUESTION. WHAT ARE YOUR EARLIEST RECOLLECTIONS OF UNDERSTANDING THAT THE THEORETICAL NOTION THAT AN ATOMIC BOMB COULD BE MADE?

Well, it went this way. There was first the experiment of Hahn and Strassmann in Germany, showing a very peculiar behavior of uranium when bombarded by neutrons, which was then explained by Frisch and Meitner as indicating that the uranium nucleus splits into two parts. The news of this was brought to the United States by Niels Bohr in early 1939, and people immediately began thinking what this may mean. It was very quickly reasoned that in this splitting, in this fission, an enormous amount of energy would be liberated. That could simply be deduced from the measured masses of the nuclei involved, and from Energy equal to MC squared, which is a very small, and very incidental part of the picture. Ah, the, so very soon it was shown that indeed a large amount of energy is released. And then it was shown also on the basis of previous logical arguments, that in the fission, neutrons would be liberated. Now if that were so, anybody could conclude if neutrons are liberated, then there can be a chain reaction. And I believe the idea of a chain reaction was conceived simultaneously by at least half a dozen people. All of this was discussed very openly. It was great news. So, in January of '39, we all were aware that a chain reaction was possible in uranium. Then it was only one more step to put these things together. The chain reaction would release a lot of energy, and so if you could make it go, you could convert this energy into power, and make power reactors. And if you were able to make the chain reaction go very quickly, then you would get an explosion. Intense. The possibility of a powerful explosion, more powerful than anything we had known before. That was pretty well common knowledge among physicists in this country, in England, in Denmark, and in Germany. There was a meeting in, I think it was in March of 1939 in Washington. This was one year of an annual meeting which took place in Washington, sponsored by the Carnegie Foundation. Carnegie Institution, I think it is called. This meeting usually was open to the press, but because of the possibility of a nuclear weapon, the sponsors of the meeting excluded the press from this particular session. And that particular session, as I said, probably in March of '39, it was generally discussed that this discovery could lead to a weapon of unbelievable power.

WAS HEISENBERG IN THIS COUNTRY FOR THAT MEETING?

Heisenberg came to this country long after that meeting. I believe we probably would not have invited him to that meeting, because it was quite clear that there would be war between Germany and the West very soon. Heisenberg came to this country in July of 1939, and maybe it was June and July, I'm not sure. And came mainly for a scientific visit, but while he was here, there was a good deal of discussion of the possibility of using uranium to make a powerful bomb. And I think at that time, he was quite willing to talk about it. He shared our opinion that probably was, there would be war. He said at that time that he thought Germany would lose the war. He did not want to stay in the United States, even though a very attractive offer was made to him by Columbia University.

SO WHEN HE WENT BACK TO GERMANY, AND ATOMIC BOMB RESEARCH STARTED IN THIS COUNTRY, WAS THERE A FEELING THAT THE SCIENTISTS IN THIS COUNTRY WERE COMPETING DIRECTLY WITH PEOPLE YOU KNEW, WITH HEISENBERG, WITH VON WEIZSACKER, WITH THE GERMAN PHYSICISTS?

There was a feeling in this country that we were competing directly with German physicists. Some of whom we know quite, quite well. And one of the main motives for us to go into the project was to be first.

HAVING KNOWN HEISENBERG AND SOME OF THE OTHERS, DID YOU FEEL THAT THEY WOULD WORK WILLINGLY FOR THE NAZIS OR WHAT WAS YOUR CONCERN?

Well, we knew that Heisenberg was against the Nazis. But we also knew that Heisenberg was a patriotic German. Much later on, it was investigated in detail what happened in Germany and there were quite a number of competent scientists who wanted very much to make an atomic bomb. One of them was Harteck the first person who was able to produce large amounts of heavy water. And heavy water is a material which may be very useful for making a nuclear reactor. That we knew only later. But we were sure that there would be enough Germans who would be willing to work on it. It was later on said by Heisenberg that he never wanted to make an atomic bomb. He only wanted to make a power reactor. And in fact he was very astonished when he heard about the explosion of the first atomic bomb over Hiroshima. His first reaction was, "It's impossible. No country can do that so fast."

ALL RIGHT. I WANTED TO ASK YOU A LITTLE BIT ABOUT YOUR DAYS AT LOS ALAMOS. DO ANY STORIES COME TO MIND THAT ILLUSTRATE THE CONFLICT BETWEEN THE SCIENTISTS AND THE MILITARY PEOPLE ON THE MANHATTAN PROJECT?

Well, there was a certain amount of conflict between the military and the scientists with variations. Oppenheimer, the director of the laboratory, got along quite well with General Groves, who was the overall director of the Manhattan Project. But, on a small scale, there were conflicts. We sometimes were troubled by the over zealous guards, who guarded the entrance to the technical area and who guarded the entrance to the Los Alamos Project as a whole. We were troubled by incompetence on the part of the military. For instance, the military ran the power plant and we had requested a power plant of a certain size and the military, of course, didn't know what we were supposed to do. And so the only use of a power plant they could think of was to power light and therefore, they put into every office one bulb of 300 watts up in the ceiling, so that it would produce a minimum of light where it was needed, but use the maximum of electricity. Of course, we wanted the electric power for our experiments, which needed a lot of it. We were somewhat surprised, again, with the electricity that the, the frequency of the alternating current which we were getting, was not 60 cycles per second, but it was 65 or so. Why was that? Well, first of all, what consequence did it have? We had lots of electric clocks and they were racing ahead, gaining about an hour each day. And so we complained about it. So, the sergeant who was in charge of the power plant said, "Well, you people tell me that as the power goes down from the power plant to your experiments, it loses some wattage, some power rating, and so I wanted to compensate for that. And so I thought it would be good to give it higher frequency." So we concluded that he didn't know much about electricity, and still was put in charge of the power plant.

I HADN'T HEARD THAT STORY BEFORE. THAT WAS INTERESTING.

I like it.

WERE THERE ANY SECURITY PROBLEMS IN TERMS OF, DID THE SCIENTISTS FEEL THAT THEIR WORK WAS HAMPERED BY THE SECURITY REQUIREMENTS?

Ah, I didn't feel that way. I didn't feel that our work was hampered by security requirements. The point was that we had strict security with regard to anybody outside so we couldn't talk to the people at the Chicago laboratory or the Oak Ridge laboratory, and so on. But Oppenheimer had made it a condition that internally there should be complete freedom of exchange between all the scientists. And so we internally, we could have as many discussions as we liked and since we had scientists of all possible fields in the laboratory, we were convinced that any question we could ask could be answered by somebody in the laboratory. In addition to that, we had a few outside consultants. Notably John von Neumann who came in every three months or so, and who gave us a lot of news from the outside that was technically important for our progress.

YOU WERE AT THE TRINITY TEST?

I was at the Trinity Test. I was not in among the group which prepared the Trinity Test, so I was not there preceding the test. But some 60 of us were taken, the group leaders generally, were taken down to the neighborhood of the Trinity Test. I think we were 20 miles away, but it may have been only ten. Ah, so we were deposited at a place from which we could observe the test very well, and, but, were not directly involved in the direction of the test.

WHAT ARE YOUR STRONGEST MEMORIES OF THE TRINITY EXPLOSION?

Well, it was an awesome site. It was incredible and even if we had, even though we had carefully calculated beforehand how much energy would be liberated, we knew that there would be a very bright ball of fire. One thing we had not thought about was that the ball of fire would drag up a lot of dust from the desert, and that, therefore, we would get an immense cloud of whirling dust with strong light in it. So, it was somewhat different from what we, from what I had expected. But the main impression was that it was tremendous.

I WANTED TO ASK YOU SOMETHING ABOUT THE PERCEPTION OF THE SOVIET UNION DURING THE WAR. I KNOW YOU MENTIONED EARLIER ABOUT BOHR TALKING IN LOS ALAMOS. WAS THERE A FEELING THAT THIS WEAPONS, THE ATOMIC WEAPONS WAS BEING DEVELOPED PARTIALLY WITH THE SOVIET UNION ABOUT TO EMERGE AS THE ENEMY ONCE THIS WAR WAS OVER? WAS THERE ANY COGNIZANCE OF THAT?

To my recollection, there never was an idea, at least among the Los Alamos scientists that the atomic weapon was being developed partly against the Soviet Union. On the contrary, we followed the progress of the Soviet Union army, after Stalingrad with great enthusiasm, very much admiring their courage and competence, and I think until nearly, well until the end of the war, it never occurred to us to consider the Soviet Union as an enemy.

WHEN IN YOUR RECOLLECTION DID THAT PERCEPTION OF THE SOVIET UNION BEGIN?

The perception of a conflict with the Soviet Union began in the fall of '45. I remember in fact, one journey from Los Alamos back to Cornell to discuss the future of the physics department here when we were very much disturbed by the constant attacks by the Soviet... the Soviet officials on especially, on England. The...

COULD I ASK YOU TO START THAT SENTENCE AGAIN. YOU STARTED TO SAY YOU WERE VERY DISTURBED BY THE CONSTANT ATTACKS OF...

Yes. We were disturbed reading in the newspaper that Stalin...

I'M SORRY. I'M GOING TO ASK YOU TO START AGAIN BECAUSE I THINK MY VOICE WAS STILL THERE WHEN YOU STARTED...

We were very disturbed, I was very disturbed reading in the newspaper in September or October of '45 of the constant verbal attacks by Stalin and the lower officials of the Soviet Union. Especially against England at the time. And later of course, there were also attacks on the United States. So, in my recollection, the cold war began by verbal attacks on the Soviet Union against the two main Western powers.

DURING THE WAR IN LOS ALAMOS, THE PERCEPTIONS OF THE SOVIETS WERE AS AN ALLY. GENERAL GROVES HAS SAID, AT LEAST IN HIS MEMOIRS, THAT THERE WAS NO DOUBT IN HIS MIND THAT THE SOVIET UNION WAS OUR ENEMY, NOT OUR ALLY.

I was aware that General Groves considered the Soviet Union a potential enemy. In fact, as I remember it, he considered them as a worse enemy than Nazi Germany. And I suppose that this idea was shared by many people in the military. I later on learned also of the experiences of some military missions of the United States in the Soviet Union when they were delivering goods to the Soviet Union but at the same time were very much mistrusted.

OK. DID YOU, LIKE NIELS BOHR, DID YOU ANTICIPATE THAT WHEN THE SOVIETS WERE NOT APPRISED OF OUR DEVELOPING ATOMIC WEAPON, THAT AN ARMS RACE WOULD ENSUE ONCE THE WAR WAS OVER?

I was not aware of that during the war. However, I was very much aware after the war that the Soviet Union would acquire nuclear weapons in the near future. We estimated then, in five years. And I remember very vividly that I expected that maybe in ten years, there might be a nuclear war between the Soviet Union and the United States.

WERE YOU SURPRISED THAT THAT HASN'T HAPPENED?

As of now, I am not surprised that this didn't happen because the statesmen were sufficiently wise to know what a nuclear war meant. And so I think we should give credit to the statement of both sides that they never ever came even close to a nuclear war with the Soviet Union.

WHEN YOU HEARD THE NEWS THAT THE BOMB HAD BEEN USED IN HIROSHIMA AND THEN IN NAGASAKI, COULD YOU DESCRIBE YOUR REACTIONS AND YOUR FEELINGS ABOUT IT?

Well, my first feeling, I'm sorry to admit was one of pride. That probably this would end the war. And that we had contributed so much to the end of the war. My second feeling came after we saw the, the films which had been taken over Hiroshima a little later by our planes. And the destruction which we saw on these films was really absolutely terrible. And although we had calculated it beforehand, just what the destruction would be, seeing it...

I'M SORRY, WE HAD SOME NOISE IN THE HALL...

I think a seminar is finished.

IF YOU DON'T MIND... LET ME JUST ASK THE QUESTION AGAIN ABOUT YOUR REACTION TO THE NEWS OF HIROSHIMA AND THEN NAGASAKI.

Well my first reaction to Hiroshima was that, was a feeling of pride. This would probably end the war, which we all wanted very, very much. And pride because we had been instrumental in bringing this about. My second reaction came when we saw films which had been taken, by an observation plane which flew over Hiroshima a few hours later. And which photographed the terrible destruction of the city. We had calculated beforehand how much destruction there would be, but seeing it on the film, seeing it more or less directly was so much more terrible. And then the later reports of course, were even worse.

WHAT ABOUT THE NAGASAKI BOMB?

The Nagasaki explosion did not make a great impression on us. At least on me. I knew it would happen. I, and it was overshadowed very quickly by the Japanese surrender. That was the great news.

WHAT ABOUT THE REACTION TO NEWS OF HIROSHIMA IN LOS ALAMOS IN GENERAL? I HEARD SOMEWHERE THAT PEOPLE HAD THOUGHT THEY WERE GOING TO HAVE A CELEBRATION BUT THEY REALLY...

I know very little about the rest of the, about the reaction in Los Alamos generally. I don't recall even the plan of having a celebration.

WHEN THE WAR ENDED. AND EUROPE, THE MISSION OF LOS ALAMOS WAS ACCOMPLISHED. THE WAR HAD BEEN WON, DID YOU FEEL ANY OBLIGATION NOW, AS A SCIENTIST, TO INFLUENCE POLICY?

Many of us, when the war had been won, thought of what to do next. And the, we were convinced that we knew a great deal more of the possible effects of a nuclear war and that we should therefore tell the people of the United States what these effects would be. And that we should never have an atomic war. That there should never be another nuclear bomb set off in anger. So, many of us felt it our obligation for one thing, to travel around the country and give speeches pointing out the dangers of nuclear war and for another thing, advocating international control of nuclear weapons. We also felt that we should try to influence the government and in particular, the Congress. There were very massive, groups where very large numbers of scientists who went to Washington and stayed there for considerable time in order to talk to Congress and testify on nuclear weapons. Our main aim, our main aims were two. In testifying to Congress, our aim was to get civilian rather than military control of nuclear energy. And in general discussions, it was to support the plan to have international control.

SO DID, IN YOUR ESTIMATION, DID THE EXISTENCE OF THE ATOMIC BOMB FOSTER A NEW KIND OF RELATIONSHIP BETWEEN SCIENCE AND POLICY MAKERS IN GOVERNMENT?

Yes, I thought that the...

WHY DON'T YOU START AGAIN.

I thought that policy makers should consult scientists from now on, until further notice, very thoroughly about the nature of nuclear weapons, what to do with them, how to control them and that scientists should be consulted.

THIS WAS A NEW DIMENSION.

This was a new idea. We had never asked to be consulted by the government, except in the plans to set up the research laboratories during, during the war. But it was a new idea to be consulted during peacetime.

DO YOU THINK THAT THE BIKINI TEST WHICH HAPPENED APPROXIMATELY THE SAME TIME AS THE BARUCH PLAN WAS BEING DISCUSSED IN THE UNITED NATIONS -- WAS THE BIKINI TEST DETRIMENTAL TO THE CAUSE OF INTERNATIONAL CONTROL?

I didn't think so at the time that the Bikini Test was detrimental and, but I can't tell.

DO YOU THINK, DID YOU AGREE WITH THE FEELING THAT CONTINUED TESTING WAS NECESSARY?

I didn't think the Bikini Test was terribly necessary. We had calculated what would happen to ships at sea under the influence of an atomic weapon, and I didn't think that it was essential to test that. However, I had no real objections to that test, but I also wasn't asked.

WHAT WERE YOUR FEELINGS THEN ABOUT THE BARUCH PLAN AND THE CHANCES FOR ITS SUCCESS?

I WANTED TO ASK YOU, DO YOU THINK THAT AFTER THE WAR, DURING THE TIME OF THE BARUCH PLAN, WAS THERE ANY WAY THAT IT COULD HAVE SUCCEEDED? WAS THERE ANY WAY THAT AN ARMS RACE COULD HAVE BEEN AVERTED AT THAT DATE?

I certainly do not know whether an arms race could have been averted in 1946. I think the plans of the U.S. government were good. I think it was certainly worthwhile to attempt to make nuclear weapons international. The original as developed by the Lilienthal Committee, was a very generous and good plan. And this was endorsed by Dean Acheson, who was then Undersecretary of State. It was made somewhat less promising by Baruch, who then presented it to the United Nations because he emphasized the punishment for any violation of the plan, rather than the positive sides of the plan. It could have been presented let's say by Mr. Lilienthal, or by Mr. Acheson in a way which would have made it much more attractive. Nevertheless, I believe it was a foregone conclusion that the Russians would reject the plan. The Soviet Union had started work on nuclear matters and nuclear work was back in '43. Quite a long time ago. They were terribly insistent on their own determination of their fate on the right of each nation to be it's own master, and against a super-national agency. So it probably could not have succeeded. On the other hand, one should remember that there was a technical commission appointed by the United Nations, which considered very carefully whether the Lilienthal Plan had, I purposely call it the Lilienthal Plan and not the Baruch Plan, could be implemented. Ah, the commission, I think had eleven members from various nations. And in the end it agreed on a report, yes, the plan could be implemented. And I think it is very much to the credit of the Soviet delegate, to have persuaded his government to let him agree to this. Then the political people, of course, rejected the plan. I think there was little possibility that it could have succeeded. It was important that essentially all the Western countries were in favor of the plan. The United Nations at that time, of course, had a majority of countries which were in the Western bloc. That has changed very greatly by now. But, I think it was quite, quite a compliment to the Lilienthal Committee that all the Western countries endorsed the plan.

IS THERE ANYTHING THAT YOU WOULD LIKE TO SAY SPECIFICALLY ABOUT THE WAR YEARS AND THE PERIOD OF TIME FROM '39 TO '46. ANYTHING THAT YOU FEEL WAS MISUNDERSTOOD GENERALLY OR ESPECIALLY IMPORTANT?

I would like to say one thing about the war years. It was a desperate war. For two years, two and a half years, at least the Nazi Germany was clearly dominant. They had conquered the Western countries on the continent. They were marching essentially without much resistance into Russia. There was a great danger that Nazi Germany would win the war. There was therefore, I think every justification for the scientists of the West to work on ways to defeat Nazi Germany. And this is something which today's young people do not know anymore. They do not realize what Nazi Germany was like. That Nazi Germany was devoted to destroying all the values of Western culture. And resistance against that was essential. The, in addition to this, as far as nuclear weapons were concerned, we had every reason to believe that Nazi Germany was hard at work developing nuclear weapons. They had highly competent physicists. And a highly competent industrial base. We later on found out at the end of the war that they really had not got very far. But we couldn't know that. During the war, there was an encounter between Heisenberg and Niels Bohr which has been very much talked about, and this was totally unsuccessful. They were afraid of each other. Heisenberg tried to tell Niels Bohr that Germany was not trying to develop nuclear weapons. Heisenberg wanted Bohr to transmit this to the allies, but none of that became clear because Heisenberg was very much afraid that any such message would be transmitted to the Nazi command in Germany and thereby might cost Heisenberg his life. And certainly his job. So he was very, very unclear. Bohr on the other hand, was aware of the possibility of a nuclear weapon, and totally misinterpreted the sketch which Heisenberg gave him. Bohr thought that that sketch indicated the German plans for a nuclear weapon. In fact, Heisenberg sketched a nuclear reactor. And Bohr didn't understand this. So, it was a most unfortunate encounter. And, it was not clear to Bohr just what Heisenberg wanted.

WAS THERE ANYTHING ELSE THAT WE HADN'T TOUCHED ON THAT YOU WOULD LIKE TO? IF YOU HAVE AN AFTERTHOUGHT?

Well, I was aware when the hydrogen bomb was proposed in 1949 that this would be a perpetual danger for mankind, as indeed the atomic bomb was already. But, it certainly is...

It certainly is a great multiplication of evil if you have bombs that are a hundred times as strong as atomic bombs already were. Already the atomic bomb meant a complete difference of war from what it used to be. In war, including the Second World War, if you made a plane attack on another country as the Germans did against Britain, if you had losses of ten percent in such a sortie, it was unacceptable, because neither the machines nor the men could stand that. With the atomic bomb, this changed, because a single bomb destroyed Hiroshima and again, a single plane destroyed Nagasaki. And by going to the hydrogen bomb, a single plane would destroy the biggest cities in the world. This was terrible. It also meant after the invention of the ballistic missiles, that missiles were powerful enough to carry one million tons of TNT to an enemy country. And as we have learned in the last two years, if enough such missiles with hydrogen warheads are used against cities, it may mean permanent damage, maybe permanent destruction of life on Earth. I don't believe that it would go that far, but it will go very far and recovery from such a war would take many years.