By Paul Reynolds
World affairs correspondent, BBC News website
China confident as Communist Party holds its Congress
On a recent visit to Beijing I was struck, like other visitors, by the confidence and ambition of China.
The country proclaims this as its "peaceful rise".
It has been achieved to a significant degree on the economic front, with so many of the world's electronic goods now manufactured there in a unique type of capitalism under communism.
China's views, both as an economic power and as a permanent member of the UN Security Council, have to be taken into consideration.
But equally, Chinese worldwide policies are now coming under closer examination.
Economically, it is under pressure to increase the value of its currency, the Renminbi (RMB), in order to make its exports more expensive. And its trading partners want it to obey international rules more carefully.
Environmentally, it has to be brought into post-Kyoto arrangements if there is to be any chance of major progress on greenhouse gases. Coal is still the great fuel in China, used in everything from power stations to the samovars heating water on trains.
Diplomatically, China is no longer able to operate discreetly in the background, building up what are seen by critics as its "value-free" relationships with developing countries whose resources its wants to buy.
At the moment, China's intense desire to use the Olympic Games in Beijing next year as a symbol of its new role in the world is a window during which it is vulnerable to unusual pressure in its foreign policy.
Burma is a recent example. China did not want the Security Council to take up the issue, arguing that Burma's troubles were internal and did not rise to the level of a regional or international crisis important enough for the UN's top body.
In the end, however, amid calls for a boycott of the Olympics, it had to give some ground and agreed to a statement critical of Burma issued by the council's president.
This lacked the force of a formal resolution but it nevertheless had an impact. China felt the heat of world opinion.
A pattern of limited Chinese co-operation in world affairs has emerged. It has limits but it has advantages.
North Korea is a case in point. Here, China has put pressure on North Korea's leader Kim Jong-il and has co-operated closely with the United States.
The result has been that North Korea has agreed to shut down its reactor at Yongbyon, and to give details of its nuclear programme by the end of the year.
China also felt in a difficult position over Darfur. On the one hand, as a member of the Security Council, it was coming under pressure to impose sanctions on the Sudanese government - but it is also deeply linked to that government through oil contracts.
Its solution was to resist strong sanctions but to support peace efforts in an approach designed to avoid affecting its relationship with the Khartoum administration, while trying to placate critical opinion.
It has pursued a similar path over Iran, another country it has close ties with through oil and gas deals. It has agreed to sanctions over Iran's refusal to suspend uranium enrichment - but as with Sudan, it has managed to limit those sanctions.
"The nature of China's engagement with the rest of the world has become trickier," said Adam Ward, director of the Washington office of the International Institute for Strategic Studies.
"Its value-free and apolitical foreign policy has shown it that the deeper it gets in world affairs, the harder it gets.
"It can't have a neutral relationship with Iran as well as having one with Saudi Arabia and Israel. It can't get close to Hugo Chavez without upsetting the United States.
"It has reached the second stage of its diplomacy and is showing signs of greater awareness. When President Hu Jintao paid his last visit to Africa, he did not go to Zimbabwe but sent a junior.
"China's rise has also led to a convergence of US and EU policies towards it. Washington no longer talks about China being a strategic rival, as Bush once did, but has come closer to the European view of China as a partner.
"On the other hand, the EU is realising that it might have to be more forceful in dealing with China."
An example of this EU realisation has come with the reporting by the BBC of a complaint by the EU's Trade Commissioner Peter Mandelson.
He has accused China of discriminating against European companies, of obstructing talks on intellectual property and of putting up regulatory barriers to trade, in which it already runs a huge surplus.
China's "peaceful rise" has brought huge progress to millions of its people - and cameras and other devices for the rest of us that will probably never be as cheap again.
But it is learning that participation in world affairs is not a one-way street.
This article is part of a week of special coverage on how China is ruled.