In late May, the House select committee chaired by Representative Christopher Cox published a massive report, which was made available on the Web at www.house.gov/coxreport. Chapter 2 claims incorrectly, among other largely unsupported allegations, that through ''theft'' of information China advanced its nuclear weapons designs to be ''on a par'' with the United States.
The U.S. intelligence community concludes, in contrast, that it cannot be determined to what extent China's progress in nuclear weaponry has been due to information publicly available, to espionage or to China's own efforts, and that any such advanced designs have not yet appeared in China's nuclear forces.
This latter judgment is supported by an independent panel chaired by Admiral David Jeremiah, and by the commission chaired by Warren Rudman, who heads the President's Foreign Intelligence Advisory Board.
On July 15, the Information Office of the State Council of China published a lengthy ''refutation'' of the Cox report, entitled ''Facts Speak Louder Than Words and Lies Will Collapse by Themselves.'' That document says that indeed China has possessed nuclear weapons for the last 35 years, but it claims that this work was the product of the ingenuity of Chinese scientists, combined with widely known scientific facts about nuclear weapons and published information on foreign nuclear weapons.
The Cox report attributes China's progress almost entirely to ''stolen'' information but does not answer the crucial question of how such information can benefit China's future nuclear weapons systems, in particular if nuclear tests can no longer be carried out. (China and the United States have signed but not ratified the Comprehensive Test Ban Treaty forbidding such tests.)
Despite the China scare that the Cox report produced, the report provides no answer about whether the alleged thefts have affected or will affect U.S. national security. We believe that the answer to both of these questions is ''no.''
The only thefts which the Cox report explicitly referenced are of information about the W-70, one of the U.S.-designed so-called neutron bombs, and designs relating to the W-88 warhead of the U.S. submarine-launched Trident missiles, which was designed more than 25 years ago.
The technical community knows that China tested a neutron bomb in 1988, but there is no indication that China ever deployed such a device.
The United States developed several types of neutron warheads and deployed
those in the medium-range Lance missile and in a short-range Sprint interceptor ABM missile. (The Cox report states incorrectly that the United States never deployed a neutron weapon.) However, the United States scrapped these systems, and there is general agreement that neutron bombs are more a curiosity than a usable tool of war.
China's explicit admission of the past test of a neutron bomb in the July 15 rebuttal of the Cox report (in three lines of a 35-page document) produced a widely quoted media interpretation of this statement as a threat against Taiwan. On July 16, The New York Times published an article stating that ''the target'' of the disclosure ''was apparently Taiwan'' and that the timing of the disclosure made it significant (IHT, July 16: ''China Discloses Neutron Bomb Capability'').
While indeed Taiwan-China tensions have heightened as a result of a recent statement by Taiwan's president, there is no evidence at all, either in terms of timing or of content, that the Chinese document was anything but a rebuttalof the Cox report. The delay between publication of the Cox report and the item-by-item rebuttal, which identifies many errors of fact in the Cox report, is not unreasonable.
The W-88 story is similar. China is said to have tested a thermonuclear device employing principles somewhat similar to those underlying the W-88 design. China's weapon is larger, and there is no evidence that it is derived directly from ''stolen'' information.
The Cox report projects that China will use such information to develop a new generation of smaller nuclear warheads for possible use in multiple warheads. This may or may not be so. China never deployed multiple warhead weapons, and there is no evidence that it will.
In its modernization effort, China may use smaller warheads for its new-development land mobile missiles, which, in contrast to fixed-silo-based missiles, would be less vulnerable to a preemptive attack from the United States or Russia. But China is unlikely to incur the weight and performance penalties imposed by a super-sleek package like the Trident re-entry vehicle that puts such tight constraints on the warhead itself.
China has about 450 nuclear weapons today, of which perhaps 20 can reach the United States. That latter number is not likely to more than double in the next few decades.
In contrast, the United States has about 10,000 nuclear weapons in its enduring stockpile, of which more than half could be targeted against China.
Thus, no modernization in China's nuclear weapons could significantly affect the nuclear balance between China and the United States for decades.
There is good reason to safeguard design information about nuclear weapons to the highest standard. The Cox commission, and in particular the Rudman report, strongly criticize weaknesses in U.S. nuclear security, and this requires improvements.
The principal need for safeguarding nuclear weapons design information is to keep it out of the hands of non-nuclear-weapons states in order to avoid proliferation. Improvements in the design of nuclear weapons now in the hands of China and other nuclear weapons states are not the most significant threats to the United States.
In matters of national security, one should take time to think in order to distinguish between data officially and widely unofficially available, and what has been acquired by espionage.
One must also recognize that all nations spy on one another. In the current international order, nations collect intelligence from friends and adversaries alike in order to acquire information which nations wish to keep secret. Recently the United States has jailed Israeli and Australian spies without accusing Israel or Australia of hostile acts.
The numerous errors of fact in the Cox report, and the evident intent of many to increase tensions with China, do not serve the U.S. national security interest. The suggested remedies that erect barriers between American and foreign scientists do not address the problem and constitute a larger threat to the future of U.S. national security than do the ''thefts'' alleged by the Cox commission.