A couple of weeks ago, Dafna Linzer had a long, detailed story (and online chat) on intelligence found by German intelligence on a laptop computer stolen by an Iranian citizen in 2004. I am writing a four-part series looking at the key pieces of information: a schematic of a shaft that might be for a nuclear test, plans for an underground facility to produce uranium tetrafluoride (UF4), modifications proposed for the Shahab 3 ballistic missile and the acqisition of relatively advanced P2 centrifuges from Pakistan.
A couple of weeks ago, I started a four part series on the claims advanced by intelligence sources in Dafna Linzer’s Washington Post article. One of the questions I had concerned the modifications made to Iran’s Shahab 3, specifically “What was the diameter of the notional nuclear payload?” If the diameter is .6 m (as David Albright estimated based on publicly available photographs), the Iranians probably couldn’t build a bomb that small.
I love Paul Kerr’s work at Arms Control Today and not just because he blogs on this site. He managed to run the story down, and the answer is: No, Iran’s nuclear weapons would probably be too big for the Shahab 3.
But whether and to what extent such a re-entry vehicle design would improve Iran’s ability to deliver a nuclear weapon is unclear. The former State Department official said that a re-entry vehicle built according to the design that Libya obtained from the Khan network would be too small to hold a nuclear weapon. (See ACT, March 2004.) That acquisition has sparked concern that Tehran also may have obtained similar designs, but no evidence has emerged that Iran has actually done so.
Nevertheless, the official cautioned that “[n]ot enough is known about the Iranian bomb-making capabilities” to determine whether Iran is capable of building a warhead suitable for the re-entry vehicle described in the laptop documents.
I think a second aspect of Linzer’s story was notable, namely confirmation that the design team working on the Shahab 3 nose cone was not terribly competent. “Experts at Sandia National Laboratories,” Linzer wrote, “determined … the modification plans, if executed, would not work.”
more later …