My post earlier this week drew attention to the nuclear weapons assistance that Iran almost certainly obtained from China via Pakistan, and the astonishing possibility that China actually tested Pakistan’s first atomic bomb for it at Lop Nur in May 1990.
First, on the general question of Chinese nuclear weapons assistance to Pakistan, there’s not much disagreement among experts as far as I can tell. Michael Levi, in the book On Nuclear Terrorism that the Council on Foreign Relations published in 2007, refers to “the Chinese warhead whose design was likely exported to Pakistan” (likely weighing 1.3 tons). Langewieshe reports on p. 115 of Atomic Bazaar that A.Q. Khan’s bomb “was an implosion device, based on a simple Chinese design.”
As for Iran, Reed and Stillman say on p. 293 of Nuclear Express that A.Q. Khan sold Pakistan’s uranium enrichment technology to Iran in 1987, and that “A-bomb design and fabrication plans soon followed.” They say that those transactions have been confirmed by Khan’s “chief logistician,” B.S.A. Tahir, “from his jail cell in Manila.”
The eminent science writer Jeremy Bernstein says, in a recent review of David Albright’s Pedddling Peril: “In February 1987, the Iranian government secretly signed a deal (approved by then Prime Minister Mir Hossein Moussavi) to get some used Pakistani centrifuges of the P1 design, as well as the plans for the P2 centrifuge, the P1’s successor. The Iranians paid between five and ten million dollars. . . . The unanswered question is whether the package also included the Chinese design for a nuclear weapon that Khan had obtained. Most people I have asked are quite sure that it did. “
As regards the test that Reed and Stillman believe China did for Pakistan in 1990, Bernstein tells me he does not believe that allegation (or indeed anything at all that Reed and Stillman say). Here he disagrees with his fellow reviewer of Nuclear Express, Robert Norris, the highly regarded nuclear weapons monitor at Natural Resources Defense Council in Washington. (The third co-author, Peter D. Zimmerman, has so far not responded to my request for his opinion. Evidently he is agnostic or does not want to commit himself publicly.)
In support of his view, Bernstein referred me to a paper by a leader of Pakistan’s atomic weapons program, in which Pakistan is credited with having developed its bombs all by itself. But the rather long paper (which does contain many interesting statements) devotes just one paragraph to A.Q. Khan and makes no mention of his having stolen URENCO’s enrichment technology. So, with due respect to Bernstein whom I admire and like, it’s hard for me to see why this paper is a credible source for possible nuclear weapons cooperation between China and Pakistan. The paper also makes no mention of A.Q. Khan’s having acquired or developed an atomic bomb in parallel with the Pakistan Atomic Energy Commission’s, though as far as I can tell what Langewieshe has reported is generally accepted as fact:
“The bombs [Pakistan openly tested in 1998] were fission devices, based on either the Kahuta [i.e. A.Q. Khan] or the PAEC design, or both. . . .”
Let me now quote the main technical argument Reed and Stillman make for their belief that China tested Pakistan’s first atomic bomb, that is, the bomb A.Q. Khan’s team had built to Chinese specs: “Discussions with Chinese nuclear experts inescapably point to the Chinese nuclear test known as Event 35 as the test of a CHIC-4 derivative design,” that is, a derivative of the first atomic bomb the Chinese tested in a missile launch. “Comments regarding the May 26, 1990 event confirm the detonation of an imploded, solid-core, enriched but unboosted uranium bomb that most likely gave ten kilotons of yield, matching the performance of both the CHIC-4 shot and the subsequent May 28, 1998 test within Pakistan.”
If I understand Reed and Stillman correctly, they’re implicitly asking why China would have retested an early and rather primitive fission bomb in 1990, unless it was as a service to Pakistan. That seems a compelling argument to me, and Norris evidently agrees. Bernstein does not.
