At first Asher Karni declined to pursue the purchase of the triggered spark gaps - sophisticated switches that can be used to detonate nuclear bombs. But his Pakistani customer persisted. So on June 17, 2003, Mr. Karni, an Israeli electronics dealer living in South Africa, sent a fateful e-mail that said simply: "WILL DO."
At least that's what recently released court documents allege. Karni was arrested over a year ago when he tried to enter the US for a family ski vacation. He's since pleaded guilty to arranging illegal export of nuclear-related equipment, and agreed to cooperate with investigators to wrap up more of the ring, according to the court papers.
The question raised by the little-noticed Karni case is a frightening one: Are the proliferators proliferating? Last year Pakistani nuclear scientist Abdul Qadeer Khan publicly admitted that he had shared nuclear secrets with paying customers. Karni's confession appears to indicate that at the least there are other supplier networks out there - though perhaps not at A. Q. Kahn's level of sophistication.
Shadowy, nonstate merchants of nuclear technology have become all too common in recent years, noted the recent report of the commission on US intelligence failures. They operate under a veil of secrecy that is difficult to pull aside, cloaking their movements via front companies and international associates.
"It is the misfortune of our age to witness the globalization of trade in the ultimate weapon of mass destruction," says the report of the commission, which was cochaired by Judge Laurence Silberman and former Sen. Charles Robb.
This week many of the world's nations will debate proliferation controls at a five-year review of the Nuclear Non-Proliferation Treaty (NPT), held at the UN in New York. The NPT is supposed to function as an overarching framework for controlling the spread of nuclear weapons. Debate over the twin nuclear crises of North Korea and Iran will likely dominate the session.
But the effort to control nukes takes place at many levels, from the halls of the UN to police on the street. The case of Asher Karni shows the view from the fight's front lines.
The Karni affair began in the later months of 2002. Many of its details surfaced only in April, when the US District Court for the District of Columbia unsealed documents related to Karni's guilty plea.
Not that the case is truly over yet - federal prosecutors continue to pursue leads to other companies and individuals uncovered during their investigation. Karni has not yet been sentenced, though he likely will be soon. And his alleged customer in Pakistan - one Humayun Khan, according to court documents - has been indicted by a federal grand jury here. US authorities are trying to extradite Mr. Khan from Pakistan.
On the outside Asher Karni has long appeared to be nothing more than a prosperous dealer in electronics parts. He has lived in South Africa since 1985, when he moved there following his discharge from the Israeli army. A top salesman at an established local high-tech firm, he set up his own company, Top-Cape Technology, in 2002.
One customer he brought with him was Humayun Khan (no known relative of A.Q. Khan), head of a Pakistani firm named Pakland, which, according to the US government, specialized in obtaining electronics products of US origin.
Oscilloscopes were the first thing Humayan Khan ordered from his old associate's new firm. These devices, which display graphs of electrical signals, have many benign applications. But they can also be used to measure nuclear tests and provide other data on the nature of a warhead design. Therefore the export of sophisticated oscilloscopes is controlled by the US government.
Karni knew this, and thus had to shop around to find willing suppliers. A New York firm sent him one - but balked at a second order for 36 after Karni told them to keep quiet about the devices' end user. A New Jersey firm sent him two more, but that was it.
"Mr. Karni never obtained an export license from the Department of Commerce ... for his shipment of ... oscilloscopes to Pakistan," says a factual proffer filed in federal court in support of Karni's guilty plea.
However, the triggered spark gaps transaction may have represented a more serious violation of the law. Triggered spark gaps are switches capable of emitting powerful, precisely synchronized electronic pulses. They have civilian uses, but certain types can also be used as nuclear detonators. And Humayun Khan was asking for the type whose export was controlled by the US government.
Mr. Khan directed Asher Karni to first approach a French supplier. When this firm asked for detailed end-user information, Karni apparently had second thoughts. He sent Khan an e-mail saying he wouldn't go further.
Khan shot back an e-mail, according to US court documents: "I know it's difficult but that's why we came to know each other, please help to re-negotiate this from any other source...."
The plea must have been convincing. Karni returned to the New Jersey firm that had sold him oscilloscopes. They agreed to sell him the spark gaps. But unbeknownst to Karni, his game was beginning to unravel: The Department of Commerce had received an anonymous tip about his activities. The spark gaps were shipped in October - but only after their manufacturer had rendered them inoperable.
Asked by the shipper for the spark gaps' end user, Karni invented a fictitious South African company, Mask Technology, and a fictitious contact, one Lamar de Wet. Mask was a front, its sole employee a woman who was Karni's assistant. When contacted she simply said the nonexistent Mr. Lamar de Wet was "away on business."
The US government had had enough. On Dec. 11, 2003, South African police raided Mr. Karni's office and seized his files. One of the mysteries of the case is why Karni himself then flew to Denver with his family for vacation only weeks later. At the airport he faced inevitable arrest.
According to proliferation experts, the Karni case is notable for its scope. With other activities taken into account it involved over a dozen companies.
Its methodology, however, was typical. Generally, proliferation networks employ front firms for one or two transactions. Then they move on.
"That's what you're facing - a lot of smoke and mirrors," says Lora Saalman, a research associate at the Wisconsin Project on Nuclear Arms in Washington.
This network was unraveled. But there are certainly more out there where similar activity continues, according to Ms. Saalman. For nonproliferation officials, she says, that just shows how enormous the task is.