WASHINGTON » Declaring that an attack on one nation's computer networks “;can be an attack on all,”; Secretary of State Hillary Rodham Clinton issued a warning on Thursday that the United States would defend itself from cyberattacks, though she left unclear the means of response.

In a sweeping, pointed address that dealt with the Internet as a force for both liberation and repression, Clinton said: “;Those who disrupt the free flow of information in our society or any other pose a threat to our economy, our government and our civil society. Countries or individuals that engage in cyber-attacks should face consequences and international condemnation.”;

Her speech was the first in which a senior U.S. official had articulated a vision for making Internet freedom a plank of U.S. foreign policy. While the details were few, her remarks could have far-reaching consequences, given the confrontation between Google and the Chinese government over the company's assertion that its networks had been subject to a sophisticated attack that originated in mainland China.

Clinton called for China to investigate Google's accusation and be open about its findings. She said that the United States supported Google in publicly defying the Chinese government's requirement that it censor the contents of its Chinese-language search engine.

“;Censorship should not be in any way accepted by any company from anywhere,”; Clinton said. “;American companies need to take a principled stand. This needs to be part of our national brand.”;

This month Google announced it was “;no longer willing to continue censoring”; search results for its Chinese users, pointing to breaches of Gmail accounts held by human rights activists in China. Several other companies had also been targets of hacking, the company found. Google has avoided directly blaming the government in Beijing, and the Chinese government has sought to describe the situation as strictly a business dispute.

The Obama administration has been similarly cautious. Last week, a senior administration official said the United States would issue a “;demarche”;—a diplomatic move often used to lodge a protest—against China in the coming days. An official said Thursday that the administration would hold off to see whether the Chinese responded to Clinton's call for an explanation of the Google allegations.

The administration's dealings with China are further complicated by the American debt held by the Chinese government and issues like climate change, on which the United States is seeking its cooperation. Though Clinton said the administration would air its differences with Beijing, she said it would be in the context of a “;positive, cooperative, and comprehensive relationship”;—a clause added to her speech at the last minute.

Clinton also singled out Saudi Arabia, Egypt, Tunisia, Vietnam and Uzbekistan as countries that constrain Internet freedom or persecute those who use the Web to circulate unpopular ideas. She pointed to an Egyptian blogger, Bassem Samir, who was in the audience at the Newseum in Washington for Clinton's speech and had been imprisoned by Egyptian authorities.

Human rights groups applauded the speech, though some questioned how the United States would enforce the issues raised.

Tom Malinowski, the Washington advocacy director for Human Rights Watch, said the United States should treat China's forced censorship as an unfair trade practice, which could be confronted through the World Trade Organization or raised in future trade negotiations.

Still, Malinowski said: “;I really thought this was groundbreaking. She showed no hesitation in naming countries, including U.S. allies, for suppressing speech on the Internet. She made a very strong case for connecting Internet freedom to core American national security interests.”;

As secretary of state, Clinton has elevated the role of the Internet and digital technology in U.S. diplomacy. She named Alec Ross, a technology entrepreneur who advised the campaign of President Barack Obama, as her senior adviser for innovation.

Ross has assembled a team that is pursuing programs like a social network for young people in Pakistan and a service that lets people in Mexico file electronic reports on drug-related activity.

Clinton announced a new $15 million effort to help more young people, women and citizens groups in other countries communicate on the Web. None of the proposals she mentioned focused on China or Iran, and the financing is relatively modest.

For Cameran Ashraf, 29, an Iranian-American information technology worker who has helped Iranian protesters circumvent government filtering of their messages, Clinton's tone was enough. “;I didn't expect such strong, forceful language,”; he said. “;I was beyond pleased.”;