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Louis Rosen’s Interview

Manhattan Project Locations:

Louis Rosen, a native New Yorker and the son of Polish immigrants, was personally selected to work on the Manhattan project in Los Alamos while a graduate student in physics. Once in Los Alamos, Rosen was assigned to Edwin McMillan’s group, where he worked on implosion technology. Rosen remained in Los Alamos after the war ended and was considered the father of the Los Alamos Meson Physics Facility. Rosen describes some of the struggles he faced in his early life and explains how he and his brother were able to save up enough money to attend college, the first members of their family to do so. Rosen recalls his encounter with Dorothy McKibbin when he first arrived in Santa Fe and describes the housing that was available to scientists who worked at Los Alamos. Finally, Rosen explains some of the scientific discoveries made after the Manhattan Project and offers valuable insight on the nature of science during the height of the Cold War.

Date of Interview:
September 12, 2022
Location of the Interview:


Rosen: Well, my name is Louis Rosen. I was born in New York City, not the best part of the city. I’m now almost eighty-five years old. My parents were immigrants from Poland.  They were escaping from the pogroms, which were taking place with the Russian Cossacks coming in and raiding villages, especially where Jews where plentiful. My father came over here in about 1909. My mother—they were girl and boyfriends in the old country—came over two years later.

My father was trained as a tailor starting at ten years of age. He went to a senior tailor for training. He did a lot of work, with probably very little pay at that time. For quite some time, we had ancestors—that’s important for a reason I’ll tell you in a moment—in the so-called old country. 

One thing that always amazed me and my brother is that none of our ancestors, as far as we can determine, ever had any formal education [chuckle]. Some of them were self-taught. My father eventually became very good, not so much in English but in Yiddish, and he wrote for what was then the chief Jewish newspaper, The Forward. It’s now in English as well.

The important fact is that since we could remember, it was a given that no matter what it took, my brother and I were going to go to college. I think that’s an enormous tribute to parents like ours. I’m sorry you didn’t get to interview my brother, because he is the famous one in the family. He was for quite some years Executive Director of the Civil Service Commission. I thought when I had 400 or 500 employees, “Boy, that was plenty, he had 2.2 million!” So that’s a good part of my background.

Now, when I was very young, I remember going to school in New York City with kids from various nationalities and having to fight every day when I was five or six years old. But my father contracted tuberculosis working in the sweatshops of New York City and his doctor said, “You want to live, you’ve got to get out of here.” They had saved up about 800 dollars, which they used for a down payment on a house for the Catskill Mountains. That’s where I grew up and my brother as well.

The question was, what do you do for a living there? It was a hotel area, the so-called “Borscht belt”—Liberty, Monticello, Loch Sheldrake. We lived near Loch Sheldrake, New York. I went to a one-room school where all eight grades were taught by one teacher. There were about forty students. Each class would in turn go to the front row for the day’s teaching. The others would be in the back, they had to be quiet, but they could learn a lot from the ones who were ahead of them.

We used to walk three miles, which was not unusual in that part of the country at the time. During the winter it was rough because sometimes we had four, five feet of snow. But I was lucky. My teacher was a farmer who lived on the other side of us from the school and he would come by on horse and sleigh and I would hitch a ride with him to school, so I had it good. 

That’s the way we started our schooling. Later on, we became caretakers of one of the hotels during the winter, and so we were not so isolated. We both went to school in the little town where we had grades—well, up to about the eighth grade, we only had about two teachers, three teachers at most, for different subjects, but in high school we had teachers for different subjects. 

How did we manage to get enough money to go to college? My father was very creative and he managed to get a dealership to sell newspapers to hotel guests, and we were the ones who did the selling. We would get up at about six o’clock or five o’clock in the morning, we would get our newspapers, and then during breakfast we would go to all hotels and sell newspapers.

In the afternoon, we had an old car with a refrigerator in it and it was dry ice, and we would sell ice cream to the kids in the hotels and rooming houses. In the evening, again we would go around during mealtime and sell evening papers. So that was the way—by the time I had to go to college and then two years later my brother—we had accumulated $425 that could be made available.

I looked around for a college where I could go for that amount of money. The University of Alabama fit the bill. They had a good physics department, people from Caltech and Cornell because this was the depression; it was hard to get teaching jobs. I and my brother two year later wound up at University of Alabama. And that’s where I took my Bachelor’s degree, my Master’s, and I taught there for one semester until I could go to Penn State.

The head of the department was a person by the name of Dr. Wooten. He was a marvelous gentleman and he knew all the heads of physics departments. He got me a fellowship at Penn State which paid, as I remember, $120 a month. Well, that’s when my wife came in. She was a top-notch secretary and she got a job as a secretary, so she worked my way through graduate school [chuckle].

The War came and we were already at Penn State, so the first thing I wanted to do was enlist in the Navy. But you wouldn’t believe it, I was three pounds underweight; they wouldn’t take me. So I went back and proceeded to get my PhD degree, towards the end of which a Dr. Tritten, who was President Roosevelt’s head of scientific personnel, came to Penn State recruiting for a position he couldn’t talk about and a place he couldn’t mention, but he thought he knew what he wanted. He talked to the head of the department, Dr. Hamm was the head of the department, and he decided that he wanted me to take this job, which he couldn’t tell me about.

I knew of Dr. Tritten’s reputation. He told me that there is nothing I could do to help with the war effort which would be anywhere near as important as what he was asking me to do. So I said, “Okay, it’s a deal, what do I do next?”

He says, “You appear in Santa Fe, New Mexico as soon as possible.”

We had a one month old baby and a ’36 Ford, so we packed up our few belongings and set out for—I think it was Chattanooga, Tennessee. He told us there was not a house for the family yet, for us, but of course there would be. Qe packed up, we got in touch with Mary’s parents, and her father met us—it was one of the big cities in Tennessee—at a hotel. Mary and the baby went with him to Tuscaloosa, Alabama where I had met Mary at the university, and I trucked on with this ’36 Ford to Santa Fe.

Coming in to Santa Fe, it looked almost like a medieval village. Very crude streets, very narrow streets, mud houses. The people were not badly dressed, but you could tell they didn’t buy much clothes. I was told to proceed to 1663 [misspoke: 109] East Palace Avenue, which I did. And there, in some office number, I met Dorothy McKibbin, one of the loveliest ladies you will ever want to meet.

She told me how to get up to the Hill, and she at that point in time was also the manager of Frijoles establishment. It wasn’t a hotel but they are NYA built log cabins, which mainly the Forest Service used. But now they got rid of the forest service people and it was devoted to the scientists who were coming in who did not have a place at Los Alamos. After I got to Los Alamos, I was chauffeured down to Frijoles Canyon and there I met Dorothy McKibbin again, she was supervising the evening meal. I wasn’t there long, a few weeks, but it was delightful.

We were driven there every morning. We were picked up by some Mariners who had come to Los Alamos for rest periods, and at night they would drive us back. The thing I remember is that they had very bad nervous problems, and that’s why they were sent to rest up. They would drive very fast in order to hide the fact that they would shake all the time. It was a dirt road with potholes liberally strewn.

One day we were flying along this rode bouncing in this jeep, and here came a huge turkey. We scared it and it flew and we couldn’t avoid it. We hit it with our windshield, didn’t break the windshield but it didn’t do the turkey any good, it died.  We took the turkey in and Dorothy McKibbin cooked it for us the next day; that was a real treat. Isn’t it amazing, the things you remember?

After only a few weeks there I was told there’s a house ready for us. I think it was a two bedroom prefab house with a Black Beauty wood stove. You know, for that time and in that place, it was nothing to be sneezed at. Anyway, they told me I could bring Mary and the baby. How do you do that? Well she got on a plane in Birmingham, Alabama and was bumped in Dallas by a general. Here she was in this hotel with a baby, running out of food coupons, milk coupons. Finally, I don’t know how she did it, but she managed to get in touch with the personnel director at Los Alamos and she told him her predicament and he told me her predicament.

I said, “I have to go get her.” But at that point in time, you could only go fifty miles from Los Alamos. I told my supervisor that I just had to go get my wife and whatever penalty there is, that will be it. He said, “Well, just go ahead.” But I had to have gas coupons. So I went to Santa Fe where the coupon board resided, and I told them my predicament. They assumed that since I was going to Dallas, I must have permission from the high authorities, so they gave me the coupons. So off I went to Dallas to pick up my wife and baby, and then as fast I could I came back to Los Alamos.

I came back during one of the few rainy periods. The road up the Hill was treacherous. It was mud, it was slippery, there were no guard rails, very narrow dirt road. Mary was scared as we were driving up. She said she was never going off the Hill. I was worried about what she would think of the housing arrangements. I had the idea that I would drive up to what were hutments where the maids that were servicing the laboratories and the housing of the scientific people, where they lived. You know what they looked like; they’re just long buildings, dome-shaped buildings. They look like the devil and they were not uncomfortable inside, but they looked terrible. 

I drove up to the front of one of them and Mary said, “Is this where we’re going to live?” I didn’t say anything and she started to cry [chuckle]. So I backed up and turned around and went to our little duplex, and boy did it look good [laughter]! So that’s where we lived for about a year.

Then soon as the war ended, we moved into Fermi’s apartment, which he had vacated on Trinity Drive. These were luxury, wooden floors, central heating. There was only one problem: they put them together very fast and in many of the four, quadraplexes, only one of the apartments, the downstairs apartment, had the heat control. Sometimes they would reverse the controls accidentally, so that if it was cold and you turned it hotter, it went colder. If you were in the upstairs apartment you would yell down, “Hey, either we’re boiling or we’re freezing,” and they knew they had turned it the wrong way.

But we lived there for about a year until permanent housing became available. Mary was chairlady of the woman’s advisory housing committee. She’s a designer and an artist, and she has very good taste. She managed to design of the housing that we still live in, although we have changed it. We now have an indoor swimming pool, among other things; that was not something you even thought about in those days.

So here we are in Los Alamos. I am now assigned to Ed McMillan’s group; he is now a Nobel Laureate. His group was responsible, as you probably heard when I talked, for development of implosion technology. That consisted—in unclassified language—of finding out how to use chemical explosives in a way that you could assemble fissionable material to a dense enough state and held together for a long enough time, so that a critical mass had been achieved and remained critical for a long enough time to give a appropriate energy release. But that was a very difficult problem. 

Now the gun device, that was a given, and we didn’t have to worry about that. Well, the big surprise that we had at Los Alamos had to do with the discovery by Segre, Emilio Segre, who was one of Fermi’s students actually in Rome—the discovery that plutonium had a very high spontaneous fission rate. This meant that the assembly of plutonium would have to be done so quickly that there would not be time for a spontaneous fission to release stray neutrons, which would pre-detonate the assembly.  That was the big surprise and the major difficulty that had to be solved at Los Alamos.  It involved learning how to manufacture and fabricate and utilize chemical explosives, and that’s what I did for about a year or so.

If you read the Monitor, you’ll see a story where he tells about my extracurricular activity. Each one of the staff members was entitled to have a project that took twenty percent of the time that was not immediately related to the goal of that group, just to keep their spirits up and keep their wits sharp in terms of discovery of new ideas, new processes.

I chose a project to measure the attenuation of electromagnetic signals by high explosives when they detonate. When they detonate, they create ions. Ions are then conductors of electricity, and electromagnetic signal surrounded by a conductor gets through feebly if the conductor is really a good conductor. The question was, how good a conductor is detonating high explosives when it’s in a gaseous phase?

That’s what I worked on. Nobody really cared very much about it, but it did have some relevance to what we were doing because we had to measure the collapse time of a configuration of materials. In order to do that, you put it in a magnetic field, and when magnetic material collapses in a magnetic field, Eddy currents are produced and these can be picked up. These Eddy currents tell you how fast the collapse is taking place. That was a critical piece of information—in addition to the symmetry of the collapse—that one needed to have in order to determine what the yield would be of a certain amount of sub-critical material to start with.

So it was not entirely out of what our interests were. But it was interesting that, as near as I can tell, nobody cared about these results. But I published them every month. In fact, a few months before the test of Trinity we had to write progress reports, I think it was once a week, so these reports were available. But near as I could tell, nobody read them except the ones they were interested in, and that wasn’t one that I was doing.

But the final test before Trinity was in Pajarito Canyon. Ed Creutz’s group had been given the assignment to make a one-third scale model of the device that was going to be finally tested, and to make a final test of the collapse time so that we would be sure that a reasonable yield would result. Well, he did the experiment, as everybody was already at the Trinity Site. The collapse time was very long, and if that was really the collapse time, we would have a pre-detonation. The bomb would be a failure.

Fortunately, the head of the theoretical division was Hans Bethe. He was out there with [J. Robert] Oppenheimer, and Oppenheimer said, “Hans, go and figure out what is going on here.” And Bethe, who nobody could beat in calculating from first principles, he devised a theory but he had to anchor it. He remembered seeing these data, which I had been feeding them every month, about the attenuation of electromagnetic signals by detonating high explosives. He anchored his theory with these data and was able to tell Oppie, “Look, the chemical explosion is distorting the results that they’re getting. The distortion is such and such, and if you take out that distortion, everything is okay.”

So that was my first mini-triumph at Los Alamos. But then when the war ended, implosion studies for a while ended. I was glad of that, and I moved over to do basic research in nuclear science. I had never had a course in nuclear science, but Bethe had written three articles for Reviews of Modern Physics on nuclear physics. I had read those articles and became convinced that “Gee, you know, this has got to be the field of the future.”

I think many of us realized at that time that the world was going to run out of energy, it was going to run out of food, it was going to run out of water. But the basic requirement is energy because if you have energy you can make fertilizer, you can grow food, you can be sounding at the oceans, you can have fresh water, and you can have factories which run on energy. Solar energy was, at that time and it mostly it still is, not a viable option. I won’t go into the reasons for that—cost being one, but it’s more than the cost. 

So I decided that this had to be a very important field, and I studied my way into becoming a nuclear physicist [chuckle]. At that time, Penn State did not have a course in nuclear physics. Most universities didn’t. That is how young the science was. So I started working with the cyclotron, which had been liberated from Harvard for the war effort. It was not a very good machine, but one of the first, one of the very first. I started to study the interactions of the hydrogen and helium isotopes, because that’s fundamental. You need to know the basic interactions of nucleons before you can understand nuclei. They are made up of nucleons.

That was a no brainer, and I thought it was basic research that probably wouldn’t have any application to anything, but was I ever wrong about that [chuckle]. Because very soon after that, President Truman decided—well, first I should have told you that right after the war, it was devastating for Los Alamos Laboratory. Almost all of the senior scientists went back to their universities, which was very good for the nation—they had to train the next generation of scientists—but it was a disaster for the laboratory.

However, some of us, mainly the younger people, stayed. One of the reasons a number of us stayed was that we knew from our parents, who knew from their relatives who were still in Europe, what a horrible dictator Stalin was. We realized that this world was not going to be a safe place as long as Stalin was able to muster the kind of military might that the old Soviet Union could assemble, and that we had better not leave nuclear weaponry in its infancy.

We made the right decision because very soon it was discovered that the Soviets were working on a hydrogen bomb first. Of course they had [Klaus] Fuchs, and the greatest thing that Truman did to start with was to not make a big deal that Fuchs was a spy and he defected and he gave the Soviets information, which helped them, probably by several years, to develop the first atomic bomb. [Editor’s note: Fuchs passed nuclear secrets to the USSR, but he did not defect. He was tried and convicted in Britain in 1950 for espionage.] Had he done what was done when Wen Ho Lee was first apprehended, we would have been really in a sad situation. You know, he was a hat salesman, but he was very wise. He decided that we were just going to forget about that, that was history and we’re going to stay ahead.

Well, Truman realized—although he didn’t have an understanding of really how atomic bombs worked—he realized that if nature was such as to make nuclear energy feasible, eventually everybody would know how to do it. So our job was to stay ahead and to make sure that nobody outdid us in understanding what can be done, how it can be done, and how to take protective action against this new threat, which is absolutely bound to develop.

That was the first thing he did that made Los Alamos able to survive. But the second thing he did was, he found out through intelligence that the Russians were going to develop a hydrogen bomb. Of course, nobody knew whether it could be done, but he dictated a crash program at Los Alamos to see if a fusion bomb could be developed, and if so, to develop it.

Given the crash program to develop an H-bomb, it became possible to hire people. We did not lack for resources for the next ten or fifteen years. Norris Bradbury, in testifying before Congress, was asked by a Congressman, “Dr. Bradbury, what are you doing to save money?”

His reply was, “The purpose of the Los Alamos laboratory is not to save money. It is to spend money, but to do so wisely.” I thought that was an accurate and beautiful response. He was never again asked that question.

So here we are now working very hard. During the war we worked six or seven days a week. I still remember a story about Segre not showing up some Sundays. At one point—he was in Fermi’s group—Fermi called him in. He was a former student of Fermi, and Fermi asked him:

“Emilio, why is that I did not see you here yesterday, Sunday?”

Emilio told him, “Well, I went fishing.”

“Fishing! How can you go fishing when we have so many problems here that need to be solved?”

Segre explained to him how complex fishing is, how you have to wrap flies exactly right, how you have to stand so the fish do not see you, how you cannot talk or make any noise, how you have to decipher exactly in which hole the big fish might be. Finally, Fermi said to him, “Oh, I see, it’s a battle of wits” [Chuckle]. Well, that’s aside from the story. 

So we’re developing the H-Bomb, and then my earlier research really started paying off in two very significant ways. In the first place—as I said, that cyclotron was very old. In order to use it, we designed and the shops built a camera which had nuclear emulsion detectors all the way around, so that in a thirty-minute run you could take energy and angular distributions at all angles and energies simultaneously. This was a godsend. We could do experiments with a very recalcitrant cyclotron.

But we had to develop the techniques for recording the data on nuclear emulsions and then reading it. This took microscopes. We had to train people to be microscopists. We did this all in jig time, and pretty soon we had the largest nuclear microscopy group in the world. We became experts not only on detecting charged particles, but on using nuclear emulsions to measure neutron energies, by way of having the neutron that comes in collimated and hitting a hydrogen nucleus and the emulsion projecting it. We measured that and the angle, we know the energy.

So that so-called emulsion technique for neutron spectroscopy became a crucial part of garnering the data necessary to design thermonuclear devices, and also for detecting the first neutrons from a thermonuclear explosion at Eniwetok [Atoll], that same technique, that’s why it was so important. We worked very hard on measuring neutron spectra for many elements of interest to the fusion program.

Then in 1951, I think it was, came the critical test of whether the idea that had been developed by [Edward] Teller and [Stanisaw] Ulam for igniting thermonuclear fuel with a fission device as the energy source, whether that would really work. I think you heard me tell a story of that at the ceremony Monday.

You see, what I couldn’t have time to talk about was how risky an experiment was. However, it was the only experiment that worked to determine unambiguously whether the fusion fuel had burned and with what efficiency. Nuclear emulsions are 200 to 400 microns thick on one-by-three inch glass plates. The unbelievable thing for many people was how we were going to put those emulsions—which blacken with only a few hundred milliroentgens of radiation—when this bomb would cause radiation of thousands, tens of thousands, hundreds of thousands of roentgens. How they could survive, and how would sixteen-inch glass plates survive from the blast of a rather large, at that time, fission device?

Most people thought this was a crazy experiment. But we built enormous steel and concrete collimators to shield the plates and to collimate the beam of neutrons, and it worked. I think one of the greatest thrills that I’ve ever had in science was—we couldn’t immediately get the plates because the radiation levels were too high; we had to wait till the short-live radionuclides died down. We went in two days after the blast.

My colleague, John Allred, who’s no longer with us—he was my first graduate student to do a thesis at Los Alamos. He was driving the six-by-six and we had a monitor, a radiological monitor, with us. John was a very tall, six-foot-three, 220-pound Texan. I said, “John, what are we going to do if this car breaks down in this radiation field?”

He had a meter and he was going to tell us when we had had as much radiation as was allowable, and we would have to turn around and go back. John said, “If the truck breaks down, you won’t see me, I will disappear so fast.” That did not encourage our monitor.

Anyway, we retrieved the plates, took them to our temporary laboratory, and processed them. The next morning when Teller came in and wanted to know if we had observed unambiguously—he didn’t know it was almost two days, and he still didn’t know because all of our experiments that were supposed to look at 14-MeV neutrons, they failed. They were all electronic experiments; they were swamped by the gamma rays and fission neutrons.

Rosen: Edward Teller came in—this is my recollection. His recollection is somewhat different, I must tell you, but I can’t help it. This is where I came in:

“Have you seen 14-MeV of these neutrons.” Because that’s the signature of fusion fuel burning, the DT reaction. “Have you seen that unambiguously?”

We took the plate out of the water—which you really should never do, because it has swelled up—put it under 500-time magnification, and there were these beautiful proton recall tracks all lined up parallel to each other. They were one millimeter long, which is 14-MeV in energy.

That was the kind of thrill you get once in a lifetime. It was fantastic. So that was our contribution; first we provided data that could not have been gotten in that timeframe any other way, and then we validated that the fusion process took place. We could tell them the efficiency and everything was fine.

Coming back to Los Alamos, our nuclear emulsion group did many other things. We discovered the proton belt—high-energy, several hundred MeV protons—going in arcs from the North to the South Pole, some several hundred miles up. We did that while they were testing ICBM rockets. We persuaded the Air Force to let us substitute some of the dummy warhead with nuclear emulsion. That is a long story, but it worked and we were the first to see these protons. It has some practical importance, because you don’t want people exposed to that energy proton. You have to shield our astronauts going through those layers.

There were two more extremely significant things. In the weapons area, we provided data for a number of tests so that one can analyze what happened during the explosion of a thermonuclear weapon. We did that, and we did also for pure fission devices.

But our biggest contribution was when we discovered why one of the test explosions was much bigger than anybody had anticipated. The reason had to do with the fact that lithium-7, which is most of normal lithium, produces tritium when it’s bombarded with 14-MeV neutrons, and that one 14-MeV neutron can produce as many as three tritium nuclei. Well, that refuels the tritium in the device, and we didn’t know about that.

But it also means that a thermal nuclear reactor, if it can be built, and if you use a normal lithium shield around it, can produce more tritium than it consumes. So that was one of our great contributions. We were the first to generate polarized protons, protons which have their spins all in the same direction, because you can use that to probe certain aspects of nuclei.

Then my next really big project, which I was engaged in from 1960 ‘til the time I retired in ’85—I stepped down in ’85 but I retired in 1991—that was the development of the meson factory, and this had numerous goals. The main one was to have a magnet that would be a world-class means of attracting scientists from around the world, not only to bring scientific knowledge and expertise to the laboratory, but to cultivate world harmony by having scientists, especially from China and the USSR. In fact, even during the building and utilization of that accelerator, I spent a lot of time and effort trying to facilitate confidence-building through technological cooperation.

I was one of the original members of the US-USSR Joint Coordinating Committee for the Fundamental Properties of Matter. We would spend one year in the Soviet Union and one year in the US, and lay out collaborate programs. I think my biggest success was when the Chinese government invited Mary and me to come and visit. The deal was that if we would give three lectures, one on energy, they would take us anywhere we wanted to go. Mary decided where we would go and I provided the luggage. But the important thing was that after we had toured all these facilities and wherever Mary had wanted to go, we were met by Emissary [inaudible], who was the deputy prime minister at the time. He wanted to see us in his offices in the emperor’s palace in the secret city.

We went to see him and he welcomed us and we talked for more than an hour. At the end I told him about his facilities, what was wrong and what was right. He told me how great communism had been for China—no more hunger, no more people without a place to live, et cetera, et cetera.

Anyway, at the end he said to me, “Now Professor Rosen, you know, I am in charge of all science, education, and technology, in China. I don’t even have a high school degree. Now if you had my job and you wanted bring China abreast of the Western world in science and technology, what would you do?”

I thought for a minute, I knew this was something akin to a trap, but I had to answer. “What I would do, Mr. Prime Minister, is each year identify some hundreds of the brightest young scientists and engineers and send them to centers of excellence in Europe, and Japan, and North America not for a day, or a week, or a month, but for at least a year, so that they can become immersed in frontier science and technology and most importantly understand the environment, the social and political environment, which is necessary for science and technology to prosper.”

I thought he would be offended by this, but I didn’t care. He said to me, “Very good idea, Professor Rosen. Now will you accept some of these people at your laboratory?” [Chuckle]

That was the whole reason we were invited. It was a reason for everything that happened. Well I said to him, which he knew, “At the present time, scientists from the People’s Republic can only visit Los Alamos for fourteen days,” or whatever it was at this time. “But if you will nominate scientists who we know by their reputation, I’ll see if I can get that changed.”

I thought I’d never hear from that cat again, but three months later I got a letter. He said he nominated three or four scientists, very prominent ones, division leaders and group leaders from the Institute of Nuclear Research in Beijing, which was the foremost such laboratory in China.

I spent a year trying to make the—it wasn’t the DOE [Department of Energy], it was ERDA [Energy Research and Development Administration] at that time—understand what is involved here. I pointed out to him, “Look, if we can make friends with these 1.2 billion people, it would be worth more than all the aircraft carriers and bombers than you could possibly build. There are some risks, but isn’t it worth it?

Fortunately the head of the defense program at that time was Herman Roser, who had been our neighbor at Los Alamos. He had been in charge of the ERDA management at Los Alamos that interacted with the LANL management.

He said, “Look, I agree with you, but my middle management is going to be very hard to convince because they are risk averse.”

All bureaucrats are risk averse essentially, but Roser was not. That’s one secret of a successful manager: you have to not be worried about your job. I think the man you heard, [inaudible], I think he’s in that cater. Well anyway, it took two years but the ERDA finally agreed that the Chinese could come for up to three years, I think they said, and these wonderful people came. Their work ethics were impeccable, they were no problem in any sense, so that I would list as one of my most significant accomplishments.

After I stepped down as director of LAMPF [Los Alamos Meson Physics Facility]—I had held other positions before then—group leader, division leader, LAMPF director—after I stepped down from that, I persuaded Sig Hecker, who was then the director, that we ought to have at Los Alamos a Center for National Security Studies. Look, we’re building these bombs, we have to do that. Nuclear energy is essential for the life of this planet and so we have to do what we can about that. But shouldn’t we also be concerned about a world where weapons, nuclear weapons, would not be used? He agreed, and he set up the center and I worked there for five years.

Well, that’s a brief resume.

Kelly: Fascinating one.

Rosen: Any questions?

Kelly: I know what we’re just skimming the surface of all you’ve done and thought about all these years. I really love the whole progression and I think you know we’ll be able to use a lot of this in various contexts.

Rosen: Of course, one thing I should have emphasized and didn’t, is that so may people think that if we hadn’t developed the atomic bomb, it wouldn’t have been developed.  Nothing can be further from the truth. Ask yourself, what would be the situation if a Stalin or a Saddam Hussein or a Gaddafi were the first to develop this instrument? Just imagine. It’s horrible to imagine.

Kelly: I know you have your next interview and I’m just going to ask you a softball question, a big question.  What lessons can we learn from the Manhattan Project for today?

Rosen: I think one of the main lessons we can learn is that one should not relegate fundamental research to second-class status, even when applied research is desperately in need. The best example I have is how the fundamental research that I did was so critical to doing some of the applied research that had to be done.

The other example that I would give is that when I first went to the Soviet Union after the war, we were shown a beautiful cyclotron, sixty-inch cyclotron. At that time, sixty-inch cyclotrons were the biggest built anywhere. I asked, “Well look, when did you design this?” They said it was designed in underground bunkers during the siege of Leningrad. Now that cyclotron helped mightily for Russian science to revive itself. So those are the examples I would give you.

I think for me that is the most important lesson we can learn from the Manhattan Project: that if you want to do big things and you can get support to do them, don’t just focus narrowly on what you want to do. Have a very broad spectrum of knowledge at your disposal, because you just don’t know which piece of knowledge will be critical to achieving your objectives.

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