How Pakistan’s A.Q. Khan Helped North Korea Get the Bomb

In light of A.Q. Khan’s death on Sunday, the following is an adaptation from the 2008 book Meltdown: The Inside Story of the North Korean Nuclear Crisis.

A.Q. Khan, who died on Oct. 10 of COVID-19 at age 85, is celebrated in Pakistan as a national hero who built the country’s nuclear bomb program. Internationally, though, he became infamous not as a nuclear scientist but as a nuclear smuggler—including playing a key role in boosting North Korea’s weapons program.

As the head of Khan Research Laboratories, A.Q. Khan presided over his own nuclear fiefdom, which in the late 1980s and early ’90s spearheaded Pakistan’s development of highly enriched uranium. In 1998, Pakistan carried out a successful test of a nuclear bomb. Yet, confronted with the nuclear prowess of its neighbor and rival India, Pakistan still urgently needed a missile to deliver its bomb, and it was looking for a shortcut to avoid having to develop one on its own.

His role as the “father of Pakistan’s atomic weapons program” turned Khan into a national hero. It also emboldened him to embark on a new path: secretly selling nuclear technology, know-how, and equipment to other countries. Khan began his enterprise in the late 1980s by selling centrifuges, blueprints, and other components to Iran. He would also eventually approach Iraq and Syria, and by the new millennium his client list had expanded to include Libya and North Korea.

It is widely believed that a visit to Pyongyang by Pakistani Prime Minister Benazir Bhutto in December 1993 was the critical first step in an accelerating pattern of cooperation between Islamabad and Pyongyang. Bhutto reportedly returned home with design details for a North Korean Rodong missile. She consistently maintained it was purely a cash transaction—Pakistani money for North Korean missile technology.

Following her visit, defense contacts between the two countries multiplied, leading, in either 1996 or 1997, to the delivery by North Korea’s Changgwang Sinyong Corp. of key missile components—or possibly an entire missile. The Pakistanis eventually rechristened the 900-mile intermediate-range missile the Ghauri, after a medieval Muslim conqueror in northern India, and successfully tested it in 1998. Western analysts noted that the Ghauri was a close replica of the Rodong, although with some modifications.

By the mid-1990s, however, Pakistan was facing a financial crisis as its foreign exchange reserves plunged. It was at this point that the first real evidence emerged that Khan was offering nuclear know-how to the North Koreans. Khan reportedly visited North Korea 13 times and appears to have proposed a barter deal, under which Pakistan would compensate North Korea for ballistic missiles with uranium-enrichment technology. Some of the equipment was then transported on Pakistani military aircraft, with the flights cleared by Pakistani air controllers.

At the time, U.S. intelligence was monitoring the flights and at least some of Khan’s visits. Aware of the expanding contacts, Washington did not yet have sufficient details to put all the pieces of the puzzle together. Moreover, with the more immediate threat of Pyongyang’s plutonium weapons program frozen under the 1994 Agreed Framework deal, a possible North Korean uranium effort—which at this stage appeared to be more at the level of research and development rather than full-scale production—was not a top priority. The Clinton administration, according to officials who handled nonproliferation matters at the time, did decide, in the context of a broader thaw, to address the uranium issue with the North Koreans, but time ran out before it could do so.

In the final year of the Clinton administration, however, enough alarm bells had begun to sound about Khan’s proliferation activities that it triggered an ambitious joint U.S.-British intelligence operation to target the Pakistani nuclear scientist. The effort involved not just access to an incriminating paper trail but actually placing agents inside the Khan proliferation network.

After George W. Bush took office as U.S. president, the intelligence operation intensified. The initial target was Libya, which had become the focus for Khan’s most elaborate effort thus far, involving an order from Muammar al-Qaddafi for large numbers of centrifuges and 1.87 tons of uranium hexafluoride. Penetration of the network would lead Qaddafi to abandon his nuclear ambitions in return for better ties with the United States and Britain in 2003. Qaddafi’s turnabout also yielded an intelligence bonanza, giving the United States enough incriminating details to force Pakistan’s President Pervez Musharraf to place Khan under house arrest in early 2004 and assist in the dismantling of what was known of Khan’s network.

In 2002, however, the investigation was still at an earlier stage. But it was already giving the CIA a better understanding not just of Khan’s dealings with Libya but of the alarming fact that his network had other clients—including North Korea and Syria.

“Once we got inside that network it gave us windows into all of these countries, including North Korea,” former CIA Deputy Director John McLaughlin confirmed in an interview.

In his book At the Center of the Storm, former CIA Director George Tenet wrote, “Patiently, we put ourselves in a position to come in contact with individuals and organizations that we believed were part of the overall proliferation problem. … We discovered the extent of Khan’s hidden network, which stretched from Pakistan, to Europe, to the Middle East, to Asia. We pieced together a picture of the organization, revealing its subsidiaries, scientists, front companies, agents, finances, and manufacturing plants. Our spies gained access through a series of daring operations over several years.”

One sinister episode from 1998 provides a revealing glimpse of the murky netherworld in which North Korea’s nuclear acquisitions operatives—and their adversaries in Western intelligence services—operated. On June 7, 1998, 10 days after Pakistan’s first underground nuclear test, a North Korean woman named Kim Sa Nae was shot to death a few yards from Khan’s official residence in an upscale neighborhood of Islamabad. Officially, Kim was identified as the wife of Kang Thae Yun, a midlevel diplomat at the North Korean Embassy.

More than a year later, though, Pakistani officials leaked word to Paul Watson and Mubashir Zaidi of the Los Angeles Times that Kim had actually been a member of a 20-person delegation of North Korean experts invited by Khan to witness the nuclear test and learn more about the construction of uranium-based nuclear bombs. Her supposed husband, Kang, officially the North Korean Embassy’s economic counselor, worked for North Korea’s state-run Changgwang Sinyong Corp., a company that continually featured in U.S. assessments of Pyongyang’s missile export business. His presence in Pakistan appears to have been linked to the trade of North Korean missiles for Pakistani uranium-enrichment technology.

Publicly, the Pakistani authorities said almost nothing about Kim’s death. When pressed, they offered vague and unconvincing accounts. One suggested she’d been accidentally killed when a gun belonging to a neighbor’s cook went off. Another said that a different neighbor had accidentally discharged a firearm while cleaning it. Privately, Pakistani intelligence sources told the journalists from the Los Angeles Times that Kim had been suspected of spying for the United States. Her contact with unnamed Western diplomats caught the attention of Pakistan’s Inter-Services Intelligence military intelligence service, which shared its suspicion with the North Korean Embassy. Her killing soon followed.

Pakistani officials told the reporters that three days after Kim’s death, her body was flown back to Pyongyang on a U.S.-built C-130 military cargo plane—the same kind of aircraft whose repeated flights into and out of North Korea from 1997 to 2002 had set off alarm bells among U.S. intelligence officials. The reporters were told that along with Kim’s body, the plane carried both P-1 and the more sophisticated P-2 centrifuges, drawings, sketches, and technical data for centrifuges and warhead designs, as well as depleted uranium hexafluoride gas, which can be converted into weapons-grade material in centrifuges.

Reportedly, the plane was a charter flight operated by Shaheen Air International, a company set up in 1993 and run by retired officers from the Pakistani Air Force. It may not have been a coincidence that one of Pakistan’s ballistic missiles was also called the Shaheen. Named after a white falcon celebrated in Persian literature, the medium-range missile could carry conventional or nuclear payloads of up to 2,200 pounds.

By June 2002, it became clear that the Khan network had provided North Korea with the “designs for Pakistan’s older centrifuges, and for newer, more efficient models,” Tenet wrote in At the Center of the Storm.

“What was happening was, we had massive amounts of raw intelligence—signals intelligence, human intelligence … on North Korea’s massive procurement efforts to buy everything they needed to develop nuclear weapons through uranium enrichment, based on the A.Q. Khan P-2 centrifuge model,” said one former senior official with access to the information. “And so the A.Q. Khan piece tipped us off that the North Koreans had gotten the blueprints to make one of these things, including a shopping list of what you need to make it.”

“He gave them designs,” added a senior U.S. military intelligence official. “He gave them actual functioning centrifuges, both type one and type two. I think that the deal was not just to give them the technology but also the drawings and all the components of the program as well as the know-how.”

In 2006, Musharraf confirmed that Khan had given the North Koreans “nearly two dozen” centrifuges, both the P-1 and the more advanced P-2. The designations P-1 and P-2 refer to two Pakistani types of centrifuges, one more sophisticated than the other.

The designs for both had been stolen by Khan when he was working at the Dutch company Urenco in the 1970s. While such a small number of centrifuges was far short of the thousands required for the cascades necessary for nuclear weapons, with Khan’s detailed list of the remaining components, North Korea was now in a position to procure the necessary equipment to produce a uranium bomb.