Not since Mikhail Gorbachev began speaking of "Glasnost" and "Perestroika" in what turned out to be the twilight years of the Soviet Union has there been such ferment among policy intellectuals.

In Washington and Berlin, Tokyo and Paris, Seoul and New Delhi, policymakers and their advisers are arguing about what's really going on in China.

The source of the latest debate is known simply as Document No. 9, an internal Communist Party memorandum issued in April that seems to foreshadow a new kind of Cold War against the subversive menace, presented by Western ideas and "Western constitutional democracy," to Beijing's rule.

"Western forces hostile to China and dissidents within the country are still constantly infiltrating the ideological sphere," it says, a translation by The New York Times states.

The concern this has provoked among Western policymakers is echoed separately by the intense debate over China's economic prospects that is raging among Western economists and financial analysts.

The clear signs of a Chinese economic slowdown, combined with growing alarm over the stability of the Chinese financial sector, have shaken the conventional wisdom of recent years that China was on a steady course to overtake the United States and become the world's leading economy.

At the same time, Western military analysts have been sounding warnings for several years that China's decade of double-digit growth in defense spending is shifting the balance of power in Asia.

New tensions with Japan over disputed islands and with other neighbors over offshore oil rights have cast a controversial shadow of Beijing's traditional claim that it was committed to a "peaceful rise" to wealth and prosperity.

The result has been a growing uncertainty in Western capitals over the state of play in China. Its foreign policy, its military (and space) ambitions, its uncertain economic prospects and now its new political hard line have combined to sound notes of alarm that the Beijing leadership isn't prepared to be "a responsible stakeholder" in the global political economy, as former World Bank President Robert Zoellick once put it. Some even see a new Cold War in the offing.

"It's already becoming a new kind of cold war," suggested Eurasia Group President Ian Bremmer last year. "What this means is that the Americans and the Chinese will be frenemies. They're not going to become enemies, because that's not possible, but they're not friends any more, either.

"All of America's allies are very much afraid of China's rise, so they're begging the U.S. to play a more significant role in Asia."

Bremmer spoke before the concerns aroused by Document No. 9, which suggests a striking sense of defensiveness and disquiet among China's ruling elite about their grip on power. It hasn't been officially published outside the party. But echoes of this new ideological hard line against Western ideas have been erupting in local party newspapers and official websites and publications.

"Constitutionalism belongs only to capitalism," said one commentary in People's Daily, an official publication. Constitutionalism "is a weapon for information and psychological warfare used by the magnates of American monopoly capitalism and their proxies in China to subvert China's socialist system," said another commentary in the same newspaper.

Document No. 9 says the main subversive threats beyond constitutional democracy include "universal rights," Western concepts of a free press and the West's mistrust of one-party rule.

In its support for the dominant role of the party in public life it also challenges the West's belief in the importance of civil society. And it goes on to warn against critiques of the party's historical record, for example of the crushing of the student movement in Tiananmen Square in 1989, or Mao's Cultural Revolution in the mid-1960s.

The overall effect of Document No. 9 is to suggest a remarkable sense of vulnerability at the top of the Beijing power system as the Internet and blogging and the rise of a prosperous middle class rooted in the private sector all seem to threaten the party's hold, even as criticism of corruption among party officials is becoming widespread.

Political opponents, says the document, "have stirred up trouble about disclosing officials' assets, using the Internet to fight corruption, media controls and other sensitive topics, to provoke discontent with the party and government."

"Other sensitive topics" include the country's environmental woes and the controversial one-child policy, still largely in force despite some reforms, which is threatening China with a demographic nightmare of few children to support an ever-rising number of elderly.

The crucial issue is that there appears to be a growing disconnect between the interests of the party elite, committed to retaining sole power, and the interests of China and its people as a whole. They, after all, appear to enjoy the freedom of speech and comment and criticism on the internet.

And as the economy falters the party elite, with an eye on the way that Glasnost helped collapse the Soviet Union, seems to be running scared.