By REUTERS Filed at 0:56 a.m. ET WASHINGTON (Reuters) - A year after the Y2K bug, U.S. officials are once again warning about perceived dangers to a United States increasingly stitched together by bits and bytes of computer code. This time, a key stated fear is information warfare, or sneak electronic assaults that could crash power grids, financial networks, transportation systems and telecommunications, among other vital services. National security aides trace the threat to hostile or potentially hostile governments as well as drug lords, criminal cartels and increasingly computer savvy guerrilla groups. Some of these organizations ``are doing reconnaissance today on our networks, mapping them, looking for vulnerabilities,'' Richard Clarke, President Clinton's top aide for infrastructure protection and counterterrorism, told a Microsoft Corp. digital security conference in Redmond, Washington, on Dec. 8. Cyberblitzes like those that briefly knocked out major Web sites in February -- including Yahoo! Inc.'s Internet gateway, eBay Inc.'s auction service and Amazon.com Inc.'s retail site -- could easily be copied on a larger scale, said Clarke, a staff member of the White House National Security Council. ``Criminals, crackers, foreign governments -- when the new president reads that intelligence briefing, he had better move pretty fast,'' he added. Such warnings are not new from Clarke, who has frequently conjured up a ``digital Pearl Harbor,'' a reference to the Japanese surprise attack that threw the United States into the Second World War. But Clarke and other U.S. officials seem to be stepping up a public awareness campaign, spurred by the spread of information technology, growing knowledge of malicious computer code and ever greater U.S. reliance on networked systems. CYBERINICIDENT GROUP MEETS On Dec. 18, the National Security Council held the first meeting of the recently formed Cyberincident Steering Group, aimed at fostering cooperation between the private sector and government to secure systems from domestic and international cyberattack. ``This meeting was an important first step in building computer security programs for the nation,'' said Peter Tippett, chief technologist for TruSecure Corp., a leading computer security company. Among topics discussed were the creation of a rapid response system and communications between industry and government, said David Perry, the public education director for Trend Micro Inc., a maker of anti-virus products, and the co-chairman of the steering group. The U.S. intelligence community voiced its concerns last week with the release of ``Global Trends 2015,'' a wide-ranging analysis by the CIA, its sister U.S. spy shops and outside experts. The report said foes of a militarily dominant United States, rather than challenging it head-on, would seek to target an Achilles' heel in cyberspace or threaten the use of the deadliest chemical, nuclear or biological weapons. ``Such asymmetric approaches -- whether undertaken by states or nonstate actors -- will become the dominant characteristic of most threats to the U.S. homeland,'' the report, released by the National Intelligence Council, said. Over time, attacks are increasingly likely to be fired off through computer networks rather than conventional arms, as ``the skill of U.S. adversaries in employing them'' evolves, the assessment said. FBI FINGERS CHINA It said many unnamed countries were developing such technologies to complicate what the U.S. military refers to as ''power projection'' and to undermine morale at home. The interagency, FBI-led National Infrastructure Protection Center uses a slide depicting China's Great Wall in its standard presentation on cyberthreats, along with a quote from Sun Zi, author of a treatise on war in about 350 B.C. ``Subjugating the enemy's army without fighting is the true pinnacle of excellence,'' the FBI's slide quotes the ancient Chinese strategist as saying. In a telltale update, the slide includes a 1999 quote from a Chinese newspaper referring to information warfare as a means of achieving strategic victory over a militarily superior enemy.