The Bomb as illustrated in the report

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The Penney Report (1947), outlining the features of an atomic bomb based on the U.S. "Fat Man" pattern, and the tasks required to develop one for Britain, was declassified and made available to the the public under the Public Records Act. The report, appearing in the UK Public Record Office File AVIA 65/1163, "Implosion" (covering the years 1947-1953) was then withdrawn from public access during 2002 and will not be reconsidered until 2014.

The actual legal status of this file remains as a public record. Its access condition has been changed to "Retained by Department under Section 3.4" (of the PRA) which means that the file has been returned to the custody of the originating department (Ministry of Supply) or its successor. This limitation of access does not constitute reimposition of a secret security marking, and no attempt appears to have been made by the UK government to contact people who had previously obtained photocopies copies of this file, until the "Fat Man" diagram appeared on Wikileaks. The diagram and a HTML version of the text first appeared on http://nuclearweaponarchive.org/ in July 2007 but apparently remained unnoticed and unreported. The diagram was removed from the Nuclear Weapon Archive site, for political, but accordingly to the sites owner, not for proliferation reasons, in March 2008 following requests from the British Government set off by the Wikileaks exposure.

The Head of the UK Foreign and Commonwealth Office Counter Proliferation Department, Regional Issues, requested Wikileaks remove the material, stating:

Wikileaks considered the requests but did not find them to be credible. A record of the correspondence can be found in the 'Note' section of this page.

Wikileaks received the following correspondence from the British Government over diagram appearing as the first page of the document, which was released prior to the rest of the material.

From: Isabella.McRae@fco.gov.uk To: wikileaks@sunshinepress.org, legal@sunshinepress.org Subject: Nuclear bomb design information Date: Wed, 19 Mar 2008 16:07:03 +0000 (GMT) Dear Wikileaks, We have recently been alerted to the fact that you have put censored nuclear bomb designs on your website. Grateful if you could remove these as soon as possible, as I hope you agree that some censorship at least is in the public good. These designs could aid countries wishing to develop nuclear weapons, hence the desire to keep them out of the public domain. The page I am specifically referring to is: <http://wikileaks.org/wiki/First_atomic_bomb_diagram> Please let me know if you agree with me, and if you have decided to remove them. Kind regards, Isabella Isabella McRae Head, Regional Issues Section Counter Proliferation Department Tel: 020 7008 2253 Fax: 020 7008 2860 Visit our blogs at http://blogs.fco.gov.uk > P Help save paper - do you need to print this email? > *********************************************************************************** Visit http://www.fco.gov.uk for British foreign policy news and travel advice; and http://www.i-uk.com - the essential guide to the UK. We keep and use information in line with the Data Protection Act 1998. We may release this personal information to other UK government departments and public authorities. Please note that all messages sent and received by members of the Foreign & Commonwealth Office and its missions overseas may be monitored centrally. This is done to ensure the integrity of the system. ********************************************************************************** -------------------------------------------------------------------------- From: Jay Lim <editor@sunshinepress.org> Sent: 19 March 2008 16:28 To: Isabella McRae Cc: wikileaks@sunshinepress.org; legal@sunshinepress.org Subject: Re: Nuclear bomb design information Dear Ms McRaw, We take your concerns seriously. However, the editors and a number of nuclear physicists are of the opinion, which is outlined in the article summary, that our release of the material will not contribute to the the proliferation of nuclear weapons. If our argument is in error we would be happy to be corrected by a detailed response. Kind Regards, Jay Lim -------------------------------------------------------------------------- From: Isabella.McRae@fco.gov.uk To: editor@sunshinepress.org Cc: wikileaks@sunshinepress.org, legal@sunshinepress.org Subject: RE: Nuclear bomb design information Date: Wed, 19 Mar 2008 16:50:09 +0000 (GMT) Dear Mr Lim, Thank you for your prompt response. I will talk to our experts here and do my best to work up a detailed explanation for you (though some of the explanation may be classified!). I am glad to read that you have at least checked this with a number of nuclear physicists before putting it on your website. I would just add that I don't see that the information furthers your aims - i.e. reduc ed corruption, better government and stronger democracies. Therefore, I would be very grateful if you could remove the information while I work up a detailed explanation fo r you. I will try to do this as quickly as possible - I am away over Easter but if you could give me until 2 April, I'll send you something then. Kind regards, Isabella McRae -------------------------------------------------------------------------- From: Jay Lim <editor@sunshinepress.org> Sent: 19 March 2008 17:11 To: Isabella McRae Cc: editor@sunshinepress.org; wikileaks@sunshinepress.org; legal@sunshinepress.org Subject: Re: Nuclear bomb design information Dear Isabella. We will look into this. The response does not have to be a thesis, but it should be of similar effort to the argument we gave. The documents are a substantial piece of world history and have been released, then censored. Implicit in our core mission is preventing censorship of such documents. That said I don't want this guide to blind us to doing what is right. From our research I believe we have done the right thing, but as I said, we are happy to shown otherwise on an issue of such importance. Kind regards, Jay Lim -------------------------------------------------------------------------- From: Isabella.McRae@fco.gov.uk To: editor@sunshinepress.org Cc: editor@sunshinepress.org, wikileaks@sunshinepress.org, legal@sunshinepress.org Subject: RE: Nuclear bomb design information Date: Wed, 19 Mar 2008 17:30:17 +0000 (GMT) Dear Jay, Thanks for your understanding. If there is no proliferation sensitivity with this info then I can't see any problem in having it in the open domain. I need to get an expert opinion first to be confident of that. So in the mean time, to avoid doing any dam age, please do remove the info. I'll email you with a full opinion (not a thesis though) on 2 April. Kind regards, Isabella -------------------------------------------------------------------------- From: Isabella.McRae@fco.gov.uk To: editor@sunshinepress.org Cc: editor@sunshinepress.org, wikileaks@sunshinepress.org, legal@sunshinepress.org Subject: RE: Nuclear bomb design information Date: Wed, 19 Mar 2008 19:56:04 +0000 (GMT) Jay, I have had an initial assessment from our experts. They are extremely concerned by the drawing you have posted on your website and assess it is of serious proliferation concern, and possibly terrorism concern. Please remove it as soon as possible - not to do so is deeply morally irresponsible. As requested, I will work up a longer and more detailed case by 2 April. Isabella -------------------------------------------------------------------------- From: Jay Lim [mailto:editor@wikileaks.org] Sent: 19 March 2008 21:19 To: Isabella McRae Cc: editor@sunshinepress.org; wikileaks@sunshinepress.org; legal@sunshinepress.org Subject: Re: Nuclear bomb design information Without wanting to be uncharitable, if FCO's experts believe this particular document to be of "terrorism concern", we do not find them to be credible and may I suggest, neither will anyone else. Similarly after consultations it strikes us as extraordinary that the FCO claims the Wikileaks documents are a proliferation issue worthy of censorship, but, apparently, not worthy of assigning a staff member to address the issue during its Easter break. May I suggest that the FCO is engaging in busy work, pending some hyperthetical White Hall telephone call in response to the press attention our analysis of the document has received? The document has been available in one form or another since 2002, and on the internet since 2007. What has the FCO being doing in the mean time? Or are we meant to believe that states seeking to become atomic powers only read the popular press? While we will always keep an open mind on such an important issue, until we see some clear indication that the FCO takes its request that Wikileaks engage in an unprecedented act of self-censorship seriously, by telling us why we should censor, this request will not be acted on by Wikileaks. Jay Lim -------------------------------------------------------------------------- From: Isabella.McRae@fco.gov.uk To: editor@wikileaks.org Cc: editor@sunshinepress.org, wikileaks@sunshinepress.org, legal@sunshinepress.org Subject: RE: Nuclear bomb design information Date: Wed, 19 Mar 2008 21:57:49 +0000 (GMT) Jay, I'm sorry this is your view. We will be in touch in due course. Isabella --------------------------------------------------------------------------

As of Tue April 8, 2008, no further response was received.