QA问答：是什么阻止了日本在二战时拥有核武器?

Rich Anthony, Civil Engineer at Covington, KY
One thing many people are not aware of is that Japan had a serious shortage of precision machine tools and trained tool makers.
These make the tools to make things.
They had only the tools they had bought from the US and Britain prior to the war. They did not have the capacity to make more tools.

许多人不知道的一件事是，日本严重缺乏精密机床和训练有素的工具制造工厂。
即用来制造产品的工具。
他们的工具都是些战前从美国和英国购买的工具。他们没有能力制造更多的工具。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处

Michael Smith, System Administrator, Network and Hardware Design at Various, Consultant (1979-present)
Lack of knowledge and resources.

缺乏知识和资源。

Ujiyo Himura, Owner at Dark Knight Transportation (2013-present)
The same thing that prevented Germany. Lack of scientists to conduct the research needed to develop them. The Manhattan Project had thousands of scientists throughout the project. Oppenheimer had loads of help developing the theory of how the weapons would work. There were more than a few setbacks too. Nuclear physics is ridiculously complicated and it's a good thing it is. The inventory of nuclear weapons was and still is very high. These are continent disrupting weapons. Nuclear weapons are for when you absolutely need an entire city turned to glass and not just most of it flattened and set ablaze.

同样的原因阻止了德国。缺乏科学家进行开发核武器所需的研究。曼哈顿计划有数千名科学家参与。奥本海默得到了很多人的帮助来研究核武器如何工作的理论。也遇到了不少挫折。核物理极其复杂，这是一件好事。无论过去还是现在，核武器的储备量都非常高。这些都是影响世界安危的武器。核武器是在你真的决定要将整个城市融化成玻璃的时候使用的，而不仅仅是将城市的大部分区域夷为平地并将其化为火海。

Even if Japan had access to the resources, we had them first and had the initiative when it came to using them. The rest of the world looked on in horror as the United States in a matter of seconds killed 100,000+ people. Then did it again a couple of days later. Make no mistake, nuclear war is an extinction event for all life on Earth.

即使日本可以获得所需的资源，我们也比他们先一步拥有这些资源，并且在使用这些资源时拥有主动权。世界其他国家惊恐地看着美国在几秒钟内杀死了10多万人。几天后又来了一次。毫无疑问，核战争会导致地球上所有生命的灭绝。

Robert Gauthier
It is so true - those that ask why none of the Axis Powers built the bomb don’t have a good grasp of just how monumental a project doing so for the first time was. The U.S. built them first because the were the only country in the world at the time that could.

这是千真万确的——那些问为什么轴心国没有一个制造原子弹的人，没有很好地理解第一次制造原子弹是多么具有纪念意义的项目。美国首先制造出了核武器，因为当时世界上只有美国有这个能力。

Gerald Cline, former Vietnam Veteran (Medic USAF) (1968-1974)
Access to uranium and an inability to enrich the uranium even if they had had it prevented Japan from a meaningful atomic weapons program in World War II.

即使日本拥有铀，也无法进行铀浓缩，这使得日本在二战中无法进行有意义的核武器计划。

James Houk, MA History, Wright State University, Dayton, OH
Japan actually did have a nuclear program with several top flight scientists. One of these had been a favored graduate student of Neils Bohr. Japan had even purchased a cyclotron from UC Berkley. The Japanese certainly understood what had happened at Hiroshima and visiting scientists were able to calculate the yield the day after the attack. Opinion is mixed about how far the Japanese got. They had facilities in Korea which fell into Russian hands at the end of the war so some people believe they were nearly there while others believe that the Japanese were far from building a usable weapon.

日本确实拥有一个核项目，有几个顶尖的科学家参与。其中一个就是备受尼尔·玻尔喜欢的研究生。日本甚至从加州大学伯克利分校购买了一个回旋加速器。日本人当然知道在广岛发生了什么，去过广岛的科学家能够在袭击后的第二天计算出所用的核当量。对于日本人到底在这方面走了多远，人们众说纷纭。他们在朝鲜半岛拥有一些设施，这些设施在战争结束时落入了俄罗斯人的手中，所以有些人认为他们已经有能力制造核武器了，而另一些人认为日本人还远没有能力制造出可用的武器。

My own opinion is that Japan did not have the enriched uranium necessary to build a bomb. The Germans tried to send their stock of uranium to the Japanese by submarine but it never arrived. I grew up in Tennessee and visited Oak Ridge frequently enough to be very interested in the whole Manhattan Project. It was a tremendous undertaking. Huge production facilities were created to make what had never been made before. There is no indication of the reactors needed to make plutonium or the processing plants needed to chemically separate plutonium from Uranium in spent fuel rods. There is no indication of the radioactive and toxic waste that is still creating problems at American and Russian facilities. 75 years later.

我个人的观点是，日本没有制造核弹所需的浓缩铀。德国人试图用潜艇把他们储存的铀送给日本人，但这艘潜艇一直没有到达目的地。我在田纳西州长大，经常去橡树岭，对整个曼哈顿计划非常感兴趣。这是一项艰巨的任务。巨大的生产设施被用来制造以前从未生产过的东西。75年之后，已没有迹象表明，这些反应堆需要制造钚，也没有迹象表明，这些处理厂需要用化学方法将乏燃料棒中的钚从铀中分离出来。没有迹象表明，放射性和有毒废料仍在美国和俄罗斯的设施中制造问题。

At one point the Manhattan Project used more electricity than was being produced in Japan to enrich the uranium and create the plutonium that went into the bombs.. Japan did have hydroelectric plants in Korea which might have been able to separate out heavy water and power a smaller project but the footprint of any large scale facilities would have been overrun by US troops during the Korean War.

在某一时刻，曼哈顿计划使用的电力比日本生产的还要多，这些电力被用以浓缩铀和制造用于制造核弹的钚。日本在韩国确实有水力发电厂，可以将重水分离出来，为一个较小的项目供电，但在朝鲜战争期间，任何大型设施的所在地都会被美军占领。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处

George Sawyer
FWIW, Japan had at least two atomic weapons development programs. - Japanese nuclear weapon program - Wikipedia

第二次世界大战时，日本至少有两个核武器开发计划。-日本核武器计划-维基百科

Chris Rhoden, Avid interest in WW2 firearms and military doctrine
Lack of industrial capability is what kept Japan from making meaningful gains in the nuclear field. They had the scientists and basic research to make the building blocks of a program but lacked the raw industrial output to create a weapons program from it. The Manhattan Project was a massive undertaking and such a program required a number of resources that Japan simply didn't have.
I suppose another question is where the Japanese could have used the bomb itself even if they managed to make one or two. Thye had no way to reach the American mainland. Yes, they could have obliterated an American combat group or a few Chinese cities…but by mid 1944, Japan's fate was all but sealed. If anything use of Japanese nuclear weapons would have accelerated American deployment of the bomb and all but ensured an invasion of the Japanese home islands

缺乏工业能力是阻碍日本在核武器研究领域取得有意义进展的原因。他们有科学家和基础研究来成立一个研究项目，但缺乏原始的工业制造能力来完成一个武器项目。曼哈顿计划是一个巨大的事业，这样一个项目需要海量的资源，而日本根本不具备这种条件。
我想另一个问题是，即使日本人成功制造了一两个原子弹，他们又能在在哪里使用这些原子弹呢。他们没有办法将其投放到美洲大陆。是的，他们可以用其消灭一个美国航母战斗群或几个中国城市，但到1944年年中，日本的命运几乎已经确定。如果日本使用核武器，美国将加快核弹的部署，并几乎确保了对日本本土岛屿的入侵。
原创翻译：龙腾网 http://www.ltaaa.cn 转载请注明出处

George Sawyer
They could have put a bomb into a submarine and sent it into a West Coast harbor city, like San Diego.

他们可以把炸弹装进潜艇然后把它送到西海岸的港口城市，比如圣地亚哥。

Dan Tow, I have read extensively on World War II.
With good access to uranium, an enormous number of brilliant scientists, enormous natural resources, and a huge economic base, the US was barely able to build nuclear weapons in WW2, by making an enormous bet of all those resources. At the beginning of the war, Japan was way behind the US in all these measures. By the middle of the war, it was much further behind, and by the end, it had next to nothing. If Japan had made a major investment in developing nuclear weapons, the result would only have bled them dry sooner, taking resources from efforts that slowed their defeat.

由于拥有铀资源、大量杰出的科学家、丰富的自然资源和巨大的经济基础，美国在二战期间对所有这些资源下了巨大的赌注，几乎没有能力再制造核武器。战争开始时，日本在所有这些方面都远远落后于美国。到战争中期，它已经远远落后于美国了，到战争结束时，它几乎一无所有。如果日本在发展核武器上投入大量资金，从他们减缓其失败的努力中为发展核武器榨取资源，其结果只会更快的放干他们的血。

Kohhei Mugitani, lives in Japan (2008-present)
1.Uranium. At that time, Japan did not have known Uranium source. They asked Germany to provide some. In April 1945, Germany sent several hundreds kg yellow cake to Japan by U-234(Not isotope). But the U-Boat surrendered to US Navy in May. The yellow cakes was confiscated by the US.
2.Technology. Their stage still stayed in laboratory. They did not have nuclear reactor for Pu production. Still research stage for Uranium enrichment method
3.Capital. At that time, Japan did not have money, resource and industrial base.

1.铀。当时，日本还不知道铀的来源。他们要求德国提供一些援助。1945年4月，德国用U-234潜艇(不是同位素)向日本运送了数百公斤的黄饼。但这艘潜艇在5月份向美国海军投降。这些黄饼被美国没收了。
2.技术。他们的研究阶段还处于实验室里。他们没有生产钚的核反应堆。铀浓缩方法尚处于研究阶段。
3.资本。当时，日本没有资金、资源和工业基础。

Harry Hamlin, Retired bookstore owner.
Japan had a number of groups doing theoretical work, but the shortage of critical materials and inadequacy of industry placed nuclear weapons out of reach.

日本有许多小组从事理论研究，但关键材料的短缺和工业能力的不足使制造核武器变得遥不可及。

Graham Brownbill, former Professional Military Analyst at Government of the United Kingdom (1985-2015)

前英国政府专业军事分析师

Japan did not have the technical skills to develop such an advanced project.
Japan started with some very impressive systems but they then stagnated. In the US and UK the speed and breadth of development and large scale production was breathtaking. In germany steady but narrower development projects but could not produce anything in scale.
Japan by contrast achieved little new.

日本当时并不具备开发这种先进项目的技术能力。
日本一开始有一些令人印象深刻的制度，但后来就停滞不前了。在美国和英国，研发和大规模生产的速度和广度令人惊叹。在德国，拥有稳定但规模较小的发展项目，但是无法进行大规模的产品生产。
相比之下，日本几乎没有取得什么新成就。