(http://washingtonpost.com/ac2/wp-dyn/A6213-2000Oct24?language=printer).

The Pentagon is hiring 450 counterintelligence specialists to protect defense secrets after learning that China has obtained classified U.S. missile technology, including critical information about the heat shield that keeps America's most advanced missiles from burning up as they reenter the atmosphere, senior defense officials said.

While applauding the attempt to boost security, members of Congress said it was long overdue, coming more than five years after the Defense Department was told of the suspected Chinese espionage.

A trove of Chinese military documents, given to the CIA in 1995 by a former Chinese missile specialist, showed that Beijing had gathered some classified data about U.S. nuclear weapons and a great deal of secret information about America's ballistic missiles, according to officials familiar with the material.

The Energy Department reacted quickly to the apparent loss of nuclear secrets, launching a probe that focused on Los Alamos National Laboratory and scientist Wen Ho Lee. But the Defense Department has been slower to respond to what officials now say was the far more substantial evidence that China had obtained significant missile technology.

Over the past two years, Congress has pressed the Energy Department to take drastic measures to tighten security at the national laboratories, such as requiring polygraph or "lie detector" exams for thousands of employees. But little congressional pressure has been applied to the Pentagon, which now is moving to tighten its control over missile technology at military installations and private defense contractors.

Pentagon spokesman Kenneth Bacon said this week in response to inquiries from The Washington Post that it will take until 2002 to bring on board all 450 counterintelligence specialists, roughly the same number eliminated since the end of the Cold War for budgetary reasons.

"All the new specialists will work to protect technical secrets at the Defense Department laboratories and defense contractors," Bacon said, adding that "other procedural techniques and monitoring tools" will be used to improve security.

The counterintelligence officers are being hired through the Pentagon's civil service procedures and are expected to come primarily from the military, local police forces and the ranks of former government employees, according to a Pentagon official. Some will work in Washington and others at defense facilities around the country.

Sen. Richard C. Shelby (R-Ala.), chairman of the Senate Select Committee on Intelligence, said in an interview that his committee staff has been urging the Pentagon to add counterintelligence positions since 1997.

Shelby called the Pentagon's failure to investigate the loss of missile technology "a big concern." China's apparent theft of missile secrets from the Defense Department or its contractors is at least as troubling as the Energy Department's alleged loss of secrets related to nuclear warheads, he said.

Rep. Porter J. Goss (R-Fla.), chairman of the House Permanent Select Committee on Intelligence, said the slow response reflects broader security problems at the Pentagon, including a backlog of about 1 million people awaiting routine re-investigations of their security clearances.

"It is such a huge problem," Goss said. "They are whittling away at the pile there." Most of the approximately 60 espionage cases in the Defense Department over the past 20 years have involved people who had been cleared to handle classified documents. Top-secret clearances are required to be re-investigated every five years, secret clearances every 10 years and confidential clearances every 15 years.

Rep. Christopher Cox (R-Calif.), chairman of a House select committee that investigated Chinese espionage at the national laboratories, said he believes the CIA and the entire U.S. intelligence community share responsibility for the Defense Department's failure to conduct a prompt investigation of the loss of missile technology.

"The problem could have been alleviated if any member of the intelligence community had shown special initiative," Cox said.

In 1995, according to senior intelligence officials, a Chinese missile specialist approached the CIA with an unsolicited offer to provide secret Chinese military documents. Over a period of months, this "walk-in" agent handed over about 13,000 pages, The Post reported last week.

One of the first sections to be translated contained physical data about the W-88, a nuclear warhead on U.S. submarine-launched missiles. This triggered a 1996 probe by the Energy Department and the FBI, which the Justice Department later concluded had focused too narrowly on Lee.

The government never charged him with espionage, and he was freed last month after nine months in jail when he pleaded guilty to a single felony count of downloading classified data to computer tapes.

While the Energy Department and the FBI may have moved precipitously, at least in singling out Lee, the Defense Department hardly reacted at all. Government officials have suggested two reasons: The intelligence community was slow to translate all 13,000 pages from Mandarin to English, completing that work only last year, and the CIA suspected on the basis of a failed polygraph exam that the walk-in defector was a Chinese double agent.

But after the FBI brought the defector to the United States for further questioning, it concluded that he was legitimate, and senior intelligence officials said the information he provided has proved accurate.

Cox said this week that the CIA assured his committee in late 1998 that the untranslated portions were "mundane." Senior intelligence officials conceded that there were delays in translating the documents, but they said the Pentagon, the FBI and the Energy Department were informed in 1995 that China apparently had obtained classified information about the Trident II reentry vehicle on U.S. nuclear missile submarines.

"The Pentagon knew that in 1995, the FBI knew that in '95, DOE knew it," the official said.

The intelligence officials also said that since the fall of 1996, the CIA's Counterintelligence Center sent about five separate "crimes reports" to the FBI as the gradual translation of the documents yielded evidence that missile and warhead secrets had been compromised by the U.S. military or its contractors.

One former senior Pentagon official who was briefed on the walk-in documents in 1997 said the Trident II information obtained by China was "extremely accurate." It included a description of the sophisticated mating, or attachment mechanism, of the nuclear warhead inside the Mark-5 reentry vehicle, as well as of the materials that make up the heat shield.

Whether China was able to improve its own missiles because of the U.S. data remains unclear. "China's technical advances have been made on the basis of classified and unclassified information derived from espionage, contact with U.S. and other countries' scientists, conferences and publications, unauthorized media disclosures, declassified U.S. weapons information, and Chinese indigenous development," a CIA damage assessment said last year.

"The relative contribution of each cannot be determined," it concluded. But whatever its practical value, such information "should not be in Chinese hands" and most likely got there through espionage, a U.S. intelligence official said.