Detail from the photo carried in CNN’s story showing the pink tarp over the building said to contain the blast chamber.

In order to make the case for a military attack on Iran, those who advocate war need to show that Iran is engaged in developing a nuclear weapon. There will be a new IAEA report this week, and we already know that this report will try to whip up excitement around what is already known: Iran’s installation of additional centrifuges for enrichment of uranium to 20% has continued, and Iran now has increased its capacity for such enrichment. What press accounts of the enrichment situation will gloss over is the fact that IAEA inspectors are present at all of Iran’s enrichment sites and that all material is accounted for. That means that in order to accuse Iran of taking 20% enriched uranium and subjecting it to further enrichment to the 90%+ that is needed for weapons, one would have to postulate a secret site, unknown to IAEA inspectors, where Iran could take raw uranium ore all the way to weapons grade.

With the rogue enrichment route to a military attack unlikely to gain footing, war advocates also accuse Iran of other activities aimed at developing a nuclear weapon. A favorite target for those accusations is the military site at Parchin, where one particular building has been separated out and accused of holding a high explosives blast chamber where Iran is accused of carrying out research aimed at developing a neutron trigger device for a nuclear bomb. Despite a very thorough debunking of this theory by b at Moon of Alabama, where it was shown that the chamber was much more likely to be used in production of nanodiamonds than neutron triggers, the accusations continued. In May, George Jahn of AP provided ridiculous “proof” of work on a trigger device by publishing a cartoon (drawn from a real photograph!) and description of the chamber. These new allegations from Jahn even included a claim that there was a neutron detector on the outside of the chamber so that neutron flux from the explosions inside the chamber could be monitored. I showed that this allegation meant that if such work had been carried out, the steel chamber itself would have been made radioactive through the process of neutron activation. This radioactivity would be present throughout the thickness of the steel and therefore could not be removed by a surface cleaning.

Despite the fact that the steel chamber (and possibly even the structural steel of the surrounding building) would be radioactive in a way that could not be cleaned, we have for months been deluged with accusations that Iran is “cleaning” the Parchin site. After this process had gone on for some time, I began to describe it as a game of cat and mouse in which it appears that Iran is having quite a bit of fun at the expense of those who are making allegations about the Parchin site. The primary target of Iran’s pranks in Parchin is David Albright, of the Insitute for Science and International Security. Despite no known expertise in intelligence gathering by photo analysis (and that comment on lack of expertise comes from someone who previously was a CIA photo analyst) we have had multiple accounts from Albright of Iran “cleaning” the Parchin site to remove evidence of their work on a trigger device.

I have responded to most of Albright’s reports, but chose not to respond to his report of August 1, where he declared that Iran had finished its cleanup work at Parchin. That report appears to have been operational for only a brief period, however, as a report issued on August 24 shows images from August 15. In this new report, additional activity at Parchin has taken place and the suspect building is now draped with a tarp that is bright pink.

In keeping with the usual pattern for these accusations, CNN has breathlessly repeated Albright’s analysis. It hardly seems necessary to point out that the point I have been making all along still stands. The most important element of any inspection at Parchin will be the high explosive chamber itself. Iran cannot “scrub” it of neutron activation. That means that if sufficient neutron trigger work was carried out in the chamber to make it radioactive, Iran will need to remove and destroy the chamber. Whether there is a pink tarp over the building or not is irrelevant to the issue of whether the chamber still exists.

The only way Iran can top the comedic spectacle of the pink tarp is to paint the ground outside the building to mimic Albright’s yellow comment balloons and font with a note along the lines of “Please do not look at this building”.