If you want to understand why Europe needs a foreign policy, try to imagine how it looks from Zhongnanhai. I suspect China's leaders sit around in that compound next to the Forbidden City, chortling into their tea about the undignified antics of the Europeans who once plundered and humiliated their country. For today the Europeans appear like mendicants before the imperial throne, begging for business to lift their faltering economies. David Cameron for Britain, Nicolas Sarkozy for France, José Sócrates for Portugal.

Each for his own.

And human rights? European values? A Nobel peace prizewinner unjustly imprisoned? Ah yes, they did mention them, didn't they? Over dinner, that is, or in a private meeting. (The spin on this to the European leader's national media invariably oversells the brief, muted, highly diplomatic comments that historians will sooner or later discover in the official records.) Or, as Cameron did yesterday, in a carefully balanced tightrope walk before students at Peking University. (Characteristically, his speech was heavily over-spun to the British media in advance.)

Always speaking politely, of course, for is not politesse also a European value? And so discreetly that the emperor can pretend not to notice. Mentioning human rights is just one of those uncouth habits Europeans have, like picking your nose in public. Perhaps, in time, as China grows in wealth and power, the foreign devils will become more civilised.

Altogether, the conduct of European leaders is a standing invitation for any major world power to divide and rule. Putin's Russia needed no invitation. Obama's America tries to resist the temptation, genuinely looking for the single European number it can call. China is ambivalent. It's so messy and time-consuming for Beijing to deal separately with all these puffed-up, prickly little countries, and the Chinese economy benefits hugely from the existence of a single European market. But Europe's standing invitation to Chinese splittism is hard to resist.

Thus, to take a small but richly symbolic example, China is currently trying to persuade everyone – including EU ambassadors – to boycott the Nobel peace prize ceremony for Liu Xiaobo in Oslo on December 10. When it comes to Tibet or Xinjiang, China insists on the importance of total respect for its sovereignty. Yet now it is telling Europeans they should not attend a European ceremony in Europe. So China's sovereignty is absolute, other people's sovereignty is negotiable. (The United States has a similar double standard.)

This should be an easy call for Europe. The EU's 27 member states should simply announce that all their ambassadors to Norway will attend the ceremony. Basta. But in the runup to president Hu Jintao's imperial visitation to Paris last week, I read that France's foreign ministry "said it would announce before December 10 whether it intended to attend the Nobel prize-giving". Europe splits again. More tittering into the teacups at Zhongnanhai.

In Brussels last week for the annual meeting of the European council on foreign relations, a think-and-advocacy tank (on whose board I serve) devoted to developing a European foreign policy, I caught up with some of those charged with pulling together the threads of the EU's foreign policy. They observed with a mixture of irony and irritation that, in relation to China or Russia, EU member states almost invariably want the EU's collective stance to be tougher than their own individual stances.

Let no one misunderstand me here – and especially not any Chinese readers who have slipped through the great firewall to read this article. I am not for a moment saying that Europe, or the west in general, should try to impose its values on China, as it did in the past with fire and the sword.

(For an Englishman to visit the ruins of the Summer Palace in Beijing, vandalised by British and French troops, is to be filled with shame at our European barbarism.) I am most certainly not suggesting that we Europeans must get our act together because China is an enemy, as the Soviet Union was in the cold war.

No, the future of the planet depends on our having a constructive, stable relationship with this rising world power. And we do have vital economic interests in China, as China does in Europe.

I do, however, plead for a certain consistency, dignity and unity in our approach to the (re)emerging giant. I do argue that we Europeans are more likely to succeed in defending our long-term interests and advancing our values if we hang together rather than hanging separately. I further claim that what we call European values must be understood as a proposal for universal values, and that one can arrive at a belief in very similar values from the very different trajectory of Chinese history. This is exactly what the Chinese artist Ai Weiwei says. He insists that these are universal values.

China and Russia are probably the hardest cases for European foreign policy. Seen from smaller countries around the world, or from the Balkans, the EU looks stronger. A test case is coming shortly with the presidential elections in Belarus, on December 19. Will the EU have a response that is both united and effective if president Alexander Lukashenko declares himself to have won an election that he has in fact lost?

Back in the engine room in Brussels, the machinery of a supposedly single European foreign policy is only now being installed. After endless bureaucratic wrangling, huffing and puffing by the European parliament and heavy national lobbying Catherine Ashton, the EU's new high representative, has appointed four able top officials – a Frenchman, an Irishman, a Pole and a German. Of the EU's more than 130 foreign delegations, 28 have new ambassadors. For next year the new External Action Service will have a modest budget of €435m, but it can help steer the allocation of many billions in funds, notably those for development aid, of which Europe is by far the biggest donor.

A key question for Ashton is how she can bring other dimensions of Europe's economic power to bear for foreign policy purposes. Thus, for instance, China does take the EU seriously when it comes to the granting of market economy status, perhaps in a trade-off for guarantees of better Chinese respect for intellectual property rights.

As usual in the EU, everything goes more slowly and is more complicated than one would wish. At the G20 summit in Seoul there will not be a unified European voice. Next week's US-EU summit feels like a mere appendage to the Nato summit that precedes it. Angela Merkel's call for a change to the EU's Lisbon treaty, to address the problem of sovereign debt in the eurozone, risks generating more years of institutional distraction, which Europe can not afford.

Yet, to adapt the words of a leading Italian scientist, it moves. And Europe must move forward, if it is not to retreat. For even if things go well, what we Europeans achieve in concentrating our power resources will only just compensate for our relative loss of power to the re-emerging old-new giants in the east.