Beijing ? Visiting this capital after an absence of more than a decade, I felt stunned by the pace of change and by the sense of confidence, even swagger, that Chinese now feel.

The city itself is almost unrecognizable. The neo-Stalinist Beijing of squat concrete government ministries and narrow alleyways has been replaced by steel and glass office towers, shopping malls with Starbucks and suburban tracts with names like Yosemite Villas and Upper East Side.

Nationalism has supplanted communism as China’s guiding ideology. In some ways, that is not new. But before Chinese saw themselves as impoverished victims of imperialism. Now, in conversations with a range of Chinese, from high-tech executives to Communist Party reformers, I heard talk of China as a great power, ready to take a place alongside the United States and Europe.

“China’s rise is a fact,” said Ding Kuisong, vice chairman of the China Reform Forum, a key Communist Party think tank close to the Chinese president.

The forum is the author of a new initiative in Chinese foreign policy known as “China’s Peaceful Rise.” The new policy aims at making everyone else more comfortable with the rise of China, stressing its readiness to be a good neighbor ready to integrate itself into the global economy.

“We need to make contributions rather than play a role as a troublemaker,” Ding said. “We have to find ways to let our neighbors know they can benefit from China’s rise.”

This is part of a long-term calculation that China needs stability at home and abroad over the next few decades while it tackles the wrenching task of moving 1.3 billion people into the modern era. China will have to find new sources of food, energy and raw materials to feed its rapid growth, while opening markets for its goods.

The United States is of course a key market for China. But eyes here are perhaps even more fixed on the Asian neighborhood. As part of the new strategy, Ding spoke about forming an Asian community, like the European Union, an unrealistic but revealing ambition. Such a community would not exclude the United States, he reassured me. But it would eventually include an Asian currency, based on the Chinese yuan, so as not to rely on the dollar, he explained.

For a glimpse of what lies behind this ambition, listen to my discussion with a young high-tech executive. He is emblematic of the new China — an articulate graduate of American universities who returned to China passionate about the power of the Internet. He spoke unabashedly about getting rich but also about using the Internet to transform China into a more open, democratic society.

Like most I talked to here, the tech executive avoided direct criticism of the United States, other than hoping it will treat China as an “equal partner or friend.” But national pride bursts to the surface when he and others talked about their Asian rivals. He crowed about how Japan and South Korea now depend on selling their goods to China. “They know how powerful China is,” he said. “In 20 years, China will be Japan and South Korea combined.”

The Japanese remain a hated symbol for Chinese, not only for having waged war against China 70 years ago but also for their attempt to emulate the West and separate themselves from the rest of Asia. “They don’t think they are part of East Asia,” the Internet entrepreneur told me. “They think they are part of the U.S. They have to learn to treat their neighbors equally, be integrated into Asian culture. They are much closer to China than to the U.S.”

The Chinese elite rarely speak in such terms in public. They are well aware that their emergence as a great power is a growing source of anxiety for the rest of the world, most of all among their Asian neighbors.

The Chinese leadership is convinced it must integrate into the world economy and shed a Middle Kingdom mentality that ignores what others think about them. But my own sense of anxiety about where China is headed has not gone away. You don’t have to be Japanese to see how quickly China’s blistering rise can turn into arrogance and domination.

Even if it remains a peaceful neighbor — and there is good reason to think it will — China will remake Asia. And long after we stop worrying about Islamic terror, the rise of China will remain the challenge of this century.

Daniel Sneider is foreign affairs columnist for the San Jose Mercury News.