"We learned, and the Cox Commission reported, that the Chinese had acquired the design information for all U.S. thermonuclear weapons currently in our inventory," Van Cleave explained.
According to Van Cleave, the Chinese possess today the designs of all of America's nuclear weapons.
How did they get that?
"The questions of how they acquired it remain to some extent unknown," she replied.
How the U.S. lost its atomic secrets may be unknown but there are fewer mysteries in the case of Tai Shen Kuo and Gregg Bergersen. The FBI says that Kuo wanted to expand his Louisiana business into China. When he sought permission from Beijing, the Chinese asked for a few favors for their intelligence service.
The $2,000 was only part of Kuo's development of Bergersen. Kuo wined and dined his spy and Bergersen seemed to have an appetite for espionage.
At one dinner in Alexandria, Va., Kuo's tab came to $710. Kuo took Bergersen to Las Vegas for some shows. And the day of the ride that was caught on tape, Kuo brought a box of expensive Cuban cigars.
All the while, Kuo lied to Bergersen by telling him the information was being passed to Taiwan, the U.S. ally. That's a technique known in intelligence circles as "false-flagging."
"Does that make any difference in the law, whether you're spying for a hostile government or a friendly one?" Pelley asked John Slattery.
"Of course not," he replied. "Classified information's not allowed to be passed without, you know, certain approvals, to any foreign government."
"But I think when you see the information you can get out of it what you need," Bergersen told Kuo in the undercover tape. "You know, you can write all the, you can take all the notes you want."
"It's just, I cannot…ever let anyone know……because…that's my job," he said.
"I'd get fired for sure on that. Well, not even get fired, I'd go to *** jail," Bergersen added.