Tiger Trap: America's Secret Spy War With China (11 page)

Thermonuclear weapons consist of two parts, the core, or "the pit," known as the primary, a fission bomb containing either plutonium-239 or highly enriched uranium. The bomb, the size of a grapefruit, is triggered by conventional explosives, creating an implosion and a chain reaction. That in turn triggers the secondary, the much more powerful thermonuclear, or fusion, bomb. It is called a fusion bomb, or H-bomb, because during detonation, the thermonuclear fuel lithium deuteride is compressed and two isotopes of hydrogen, deuterium and tritium, fuse to rival the energy of the sun.

Alarmingly, the Chinese secret document, which bore a 1988 date, gave the exact diameter of the W-88's primary, 115mm, or about four and a half inches. Even more significantly, the document disclosed that the W-88's primary was "two-point aspherical"—a highly sensitive and, it was thought, carefully guarded US secret—which meant that it was shaped more like a football or a pear than a grapefruit, with implosion points at each end. Instead of packing a series of explosives all around a perfectly round primary, the explosives could be set off at only two points. And Beijing knew it.

It got worse. The Chinese document accurately gave the radius of the round secondary as 172mm, or just under 7 inches, and it disclosed that, unlike other nukes, the primary of the W-88 was at the tapered tip of the warhead, forward of the secondary, another secret that was supposed to be closely held.

Finally, the document accurately reported the overall length of the warhead as 1522mm, or 5 feet.
There were other documents in the walk-in's cache, hundreds that dealt with other foreign missile and defense systems, including those of Russia and France. But it was the W-88 that was, from the outset, the focus of the CIA's interest.

The W-88 warhead is the payload of the Trident II (D5) sub-based missile carried by the Ohio-class submarines, which are usually called Trident subs, after the name of the missiles they carry. Each Trident sub is armed with twenty-four missiles. The nuclear warheads are multiple independently targetable reentry vehicles (MIRVs), which means that several W-88s are released by the missile as individual targets come within range.

The importance of the W-88 is that it is small. Miniaturized nuclear bombs, unlike the huge early versions, fit into warheads that can be launched from a single missile at multiple targets. The United States was able to produce small hydrogen bombs by the late 1950s and early 1960s. US intelligence concluded that China did not test its first miniature nuclear warhead, similar to the W-88, until September 1992.

The precise number of warheads carried by each MIRVed Trident missile is secret, but is thought to be four. As many as eight, perhaps even ten, reentry vehicles, each with a W-88 warhead, could fit atop the Trident II missile, which has a range of forty-six hundred miles.

The current Trident II missiles cost $30.9 million each, are forty-four feet long, and weigh 130,000 pounds. The missile is launched underwater by gas that expands in the launch tube; when it is far enough away from the sub, the first stage ignites, an "aerospike" telescopes out to reduce drag, and the boost stage starts. In two minutes, the third-stage motor ignites, and the missile travels at the speed of twenty thousand feet per second toward its targets.

There was a fundamental reason that the W-88 document produced by the walk-in caused so much consternation inside the US intelligence community. The United States relies on a triad of nuclear weapons to deter an attack: land-based ICBMs, Air Force bombers, and nuclear-armed submarines. In the Strangelovian world of nuclear deterrence theory and mutual assured destruction (MAD), land-based missiles might be destroyed in an enemy first strike, bombers can be shot down, but submarines are relatively invulnerable. The Navy boasts that the Trident subs give the United States "its most survivable and enduring nuclear strike capability."
And now the Trident's payload, the W-88, had been compromised.

The Trident subs, known as "boomers," are huge—560-feet-long nuclear-powered ships that can travel at speeds up to twenty-five miles an hour underwater. With their crews of 155, the subs can spend two and a half months at sea. Of the eighteen Ohio-class subs, fourteen carry the Trident II missiles and W-88 warheads. Each sub has twenty-four missiles, and each W-88 has an estimated yield of 475 kilotons.

Writing in an official Navy publication, retired captain Edward L. Beach, a highly decorated World War II sub veteran and author of the best-selling 1955 novel
Run Silent, Run Deep,
described the enormous power of the Trident subs. "A single broadside from such a submarine—all 24 missiles fired at the same time—can destroy any nation on the face of the earth.
No nation—and this includes our own—could even hope to function, or even continue to exist, in the face of such a salvo."

To the intelligence agencies and the US military, China's acquisition of the design details of the W-88 meant that there had been a horrendous leak somewhere along the line. But how, when, and where was unknown. The walk-in was seen as the key; perhaps he could unravel the mystery and help the counterintelligence operators trace the leak back to its source.

But a problem soon developed. Before the walk-in could move from provisional status to that of a recruited agent, he had to be polygraphed. The CIA sets great store by the polygraph, even though the results of lie detector tests are notoriously inaccurate. Aldrich Ames, the CIA traitor who revealed agency secrets to Moscow and caused the death of ten agents—Russians working for the CIA—passed a polygraph test after consulting the KGB for advice. He was told to get a good night's sleep, come in rested and refreshed, be relaxed, calm, and cooperative, and try to establish a rapport with the examiner. It worked.

When the walk-in was "fluttered"—given a polygraph test—the CIA concluded he was lying. "When asked, 'Are you being run by another intelligence service?' his answer went off the charts,"
said one CIA officer. "Eventually the guy was practically admitting it."

The CIA decided, from the lie detector test and interrogations, that the walk-in was "a dangle," a dispatched agent under the control of Chinese intelligence. In the summer of 1996, despite the astonishing accuracy of the W-88 document, the CIA circulated an internal memo to its officers warning that some of the Chinese material was disinformation provided by a source being run by Beijing. The walk-in was not recruited.

Aside from the walk-in's failure to pass the lie detector test, the CIA concluded he was a plant because some of the documents contained information that appeared to be wrong. "At first," the CIA officer said, "he [the walk-in] said he stole the stuff, then the agency discovered there was bogus stuff mixed in, so that meant he was given material by Chinese intelligence."

There were additional reasons to be skeptical, another intelligence official asserted. "He wanted to give us more information inside China, during Chinese New Year, when nobody was on the streets. That sounded like a setup for the arrest of a [CIA] officer trying to clear a drop inside China. We didn't like the way this whole thing looked."

The FBI, however, did not agree with the CIA's analysis. "There was a woman at CIA who always says no to a source," one FBI agent said. "She's notorious for saying no. She must have a big 'No' stamp.
She pulled out her stamp and used it on the walk-in documents. She is the one who said it's a provocation, the walk-in was sent."

The bureau gave the walk-in a separate polygraph, and the FBI's China specialists decided he was exactly who he said he was. By 1999, if not earlier, the walk-in had left China and settled in California. Later, he moved to another state, where the FBI was able to locate and interview him.

To question the walk-in, the FBI sent Special Agent Doug Gregory, whom the bureau considered its most skilled interviewer, and Dave Lambert, an FBI counterintelligence agent who had worked on the Aldrich Ames and Robert Hanssen spy cases. They came away convinced that both the walk-in and his material were legitimate.

The FBI, thus reassured, continued to deal with the walk-in. The split between the two agencies, historic rivals in the intelligence world, caused a major row. To this day, both sides have stuck to their positions.

The CIA, despite its disavowal of the walk-in, was able to validate the 1988 date of the W-88 document. Whether or not the walk-in was a directed agent, his information on the W-88 was accurate.

Although the walk-in's document made it clear that China had somehow learned the measurements of the W-88, the Chinese would need more to replicate and support the miniaturized warhead. According to one intelligence official, "If the Chinese have the W-88, the next thing they would be looking for are the computer programs to maintain these systems. There is a high possibility of failure unless you understand these weapons.
They would need computer codes that simulate what would happen to the warhead with age. It has to be constantly tested over time with computer simulations. To certify that the weapons actually work."

Was China in fact able to use the data its spies acquired to build a miniaturized warhead and replicate the W-88? That was one of the key questions that the CIA faced. "The agency wrestled with this in its classified damage assessment," an intelligence official said. "An earlier 1997 study by CIA only agreed that whatever they got saved them time, maybe two to fifteen years,
and saved them resources.

"Chinese underground testing hit a peak in 1994-95 of a device somewhat similar to the W-88. You can't really tell, but you can bracket the yield, an analyst can put multiple sources together, and with the yield from seismographic information they can guess what was tested. Also you pick up a lot of SIGINT [signals intelligence]. They're chattering when a test takes place."

In May 1999 the bipartisan House committee headed by Christopher Cox issued its controversial report on Chinese espionage. The Cox Report expressed no doubts that China had taken advantage of stolen secrets. "The People's Republic of China (PRC) has stolen classified information on all of the United States' most advanced thermonuclear warheads,
and several of the associated reentry vehicles," the report asserted. "These thefts are the result of an intelligence collection program spanning two decades, and continuing to the present.

"The stolen U.S. secrets have helped the PRC fabricate and successfully test modern strategic thermonuclear weapons. The stolen information includes classified information on seven U.S. thermonuclear warheads, including every currently deployed thermonuclear warhead in the U.S. intercontinental ballistic missile arsenal."

The report also judged that China was "capable of producing small thermonuclear warheads based on the stolen U.S. design information, including the stolen W-88 information."

A number of US scientists took issue with the report and have argued that China could produce small nuclear warheads on its own, without bothering to copy American designs. However, the report included statistics that tended to support the theory that China did in fact benefit from the US technology it had somehow obtained.

The report noted that "the PRC had conducted only 45 nuclear tests in the more than 30 years from 1964 to 1996
(when the PRC signed the Comprehensive Test Ban Treaty), which would have been insufficient for the PRC to have developed advanced thermonuclear warheads on its own. This compares to the approximately 1,030 tests by the United States, 715 tests by the Soviet Union, and 210 by France."

The damage assessment by the intelligence community, while not agreeing with every aspect of the Cox Report, supported many of its major conclusions. The "Key Findings," an unclassified summary released in April 1999, found that China acquired US nuclear weapons information "by espionage" that "probably accelerated its program to develop future nuclear weapons" by allowing the Chinese to avoid dead ends in its research and development.

The summary also found that "China obtained at least basic design information on several modern US nuclear reentry vehicles, including the Trident II (W88)." China, it added, "also obtained information on a variety of US weapon design concepts and weaponization features, including those of the neutron bomb."

The "Key Findings" obliquely reflected the argument within the interagency group over whether China had been able to use the information its spies obtained. Chinese espionage, the assessment noted, had not resulted "in any apparent modernization of their deployed strategic force or any new nuclear weapons deployment." Finally, the summary concluded that China had the capacity to develop MIRVs but had not done so.

But the damage assessment, at least the portion made public, ducked another mystery. The FBI stood by its conclusion that the walk-in was who he claimed he was. If the CIA was correct that the walk-in was under the control of Chinese intelligence, why had China allowed him to deliver the W-88 document and hundreds of others?

The CIA was unable to arrive at an answer to the puzzle, but theories abounded within the intelligence agencies. One idea was that China may have been trying to rattle Washington by revealing it had acquired US nuclear secrets. In that view, the walk-in was sent to confuse or demoralize US intelligence by playing a game of "gotcha." Others speculated that the W-88 document was included by sheer accident, or to disguise the actual date when the information was acquired. Another theory held that the walk-in was part of an operation to intimidate Taiwan, which Beijing regards as part of China.

There were other theories, including one that the W-88 document was designed to support the credibility of the Chinese agent who brought it, in order to set the stage for a major deception of US intelligence. Often, a dispatched agent will hand over legitimate information to build his credibility, and then provide false information.

In the end, the experts could come up with no satisfactory answer. Whether the walk-in was sent or not, and aside from the debate about that between the CIA and the FBI, the central question remained of how China had obtained the information about the warhead in the first place. But one counterintelligence official at the Department of Energy was convinced that the W-88 details had come from Los Alamos, where the weapon was designed.