Secretary of State Hillary Clinton, in a major speech on Internet freedom two months ago, called on US technology firms not to support online censorship.

"I hope that refusal to support politically motivated censorship will become a trademark characteristic of American technology companies," Clinton said. "It should be part of our national brand."

Amid a host of trade disputes with China, however, Google's decision last week to halt censorship there met with only a fairly muted response from the State Department -- and virtual silence from other US technology giants.

Go Daddy, the world's largest registrar of Web domain names, did announce that it was no longer registering names in China because of what it called "chilling" new identification requirements imposed by the Chinese authorities.

And another domain name registrar, Network Solutions, told AFP it had stopped offering the .cn domain names in December because of the "intrusive nature" of the new Chinese policies for those seeking Web addresses.

But no other US companies indicated they were prepared to follow Google's lead and run the risk of being shut out of the world's largest online market.

Microsoft, Yahoo!, Cisco and previously Google are among the US firms which have been accused by members of the US Congress and human rights groups of abetting the Web censorship machine dubbed the "Great Firewall of China."

Yahoo! did not reply to a request for comment on Google's move but chief executive Carol Bartz said last year: "It's not our job to fix the Chinese government.

"We will respect human rights but not take on every government in the world -- that's not our mandate," Bartz said.

Microsoft for its part last week reiterated the position the software giant expressed in January when Google revealed that it and other companies had been the target of cyberattacks originating in China.

"We appreciate that different companies may make different decisions about where and how they operate their business based on their own experiences and views," a Microsoft spokesperson said.

"We remain committed to advancing free expression, and we currently are engaged actively in doing business in over 100 countries, even as we comply with the laws in every country in which we operate."

Google co-founder Sergey Brin, in an interview with Britain's Guardian newspaper, said he was "disappointed" with Microsoft and that its stance was "against freedom of speech and human rights."

While praising Google, Representative Chris Smith, a Republican from New Jersey, said Microsoft "need to get with the program and join with the side of human rights rather than enabling tyranny."

Google's decision to stand up to the Chinese authorities also won plaudits from human rights groups but it was not universally lauded and Microsoft and Yahoo! also had their defenders.

Michael Arrington, founder of US technology blog TechCrunch, condemned what he called Google's "certain level of hypocrisy" for abandoning a search market they were "failing in" while leaving behind "assets that have more promise."

Deriding Go Daddy's move a "publicity stunt," Arrington said "whatever China is or isn't, we are all very much in business with them."

"What I can't sit and watch is Microsoft being raked over the coals by a government that does nothing to fight the evil that they say exists in China," he said.

Google, Microsoft and Yahoo! are all founding members of the Global Network Initiative, which brings together Internet and telecom companies, human rights groups, academics and investors to protect freedom of expression and privacy.

Rebecca MacKinnon, a member of GNI's board of directors, noted to AFP that Yahoo! had largely disengaged from China and said Microsoft's continued presence there is not at odds with its participation in the initiative.

"The point is to try and be practical with the idea that engagement is the ideal situation if they can figure out a way to do it responsibly," MacKinnon said. "We try to get beyond the alternative of in or out.

"It would be unhelpful to say that the Chinese do a lot of bad things therefore the technology sector should disengage," she said. "Because then they should disengage from half the countries in the world."