WASHINGTON, May 25 (UPI) -- The Pentagon says Defense Secretary William Cohen is postponing his June trip to China in the wake of recent events that have cooled Washington's relations with Beijing. Pentagon spokesman Ken Bacon says, ``It's probably not the easiest time to visit China.'' Today a House committee released a damning report about alleged Chinese spying on U.S. technology. Beijing also has suspended its military contacts with the United States in retaliation for the accidental bombing of the Chinese embassy in Belgrade. Bacon said, however, the reason for the postponed trip is not the tense relationship between the two countries but the ongoing war in Kosovo. ``(Cohen's) place is here in Washington devoting as much time as possible to running the U.S. participation in NATO's air campaign,'' Bacon said today. Bacon said that the decades of Chinese access to the U.S. nuclear program was not terribly damaging to U.S. national security. Basing his comments on a CIA report on the subject released last month, Bacon said ``the distance between the U.S. and Chinese (nuclear programs) is huge.'' The United States has about 6,000 strategic nuclear missile in its arsenal. China has approximately 20 ``that may be able to strike the United States.'' Bacon said that espionage is always ``a factor in military life'' and the Defense Department devotes a considerable amount of resources to counterintelligence. Nevertheless, ``any successful espionage effort is disturbing,'' Bacon said. Last year, DOD instituted a stepped-up lab security and counterintelligence program as word of the Energy Department's lab security breeches circulated throughout the intelligence community, according to Pentagon sources.  