China's upcoming leader Xi Jinping has been wined, dined... and warned Over the past three years, the Obama administration has learned the hard way that cosying up to China is not the way to get the best out of the relationship. In 2009 Hillary Clinton began the process of engagement by effectively offering to soft-pedal on human rights before her boss, his hand weakened by the 2008 financial crisis, arrived on his maiden visit to Beijing as president and extended a hand of friendship. But what America saw as a clever diplomatic overture, China took as a sign of weakness. Anyone present in the Great Hall of the People will remember the excruciating joint statements given by Mr Obama and President Hu Jintao, in which the Chinese delivered the exact opposite of the kind of face-saving diplomatic choreography on show this week. The slap was heard around the world. That disastrous Obama visit was followed by a year in which China became increasingly strident, scaring its neighbours with a series of interventions in the South China Sea and publicly asserting the glories of its authoritarian, state-capitalist model over feckless and decadent Western economies. No mention that those same economies had gorged on the cheap goods and excessive credit that were a direct by-product of the Chinese economic "miracle" which both sides mutually acquiesced in. The response from Washington has been measured, but firm. America may be sensing its relative decline, but it is still inadvisable to take the world's most powerful nation lightly. To China's evident irritation, the US performed its "strategic pivot," declaring the South China Sea an American "core interest" and posting a symbolic force to Australia, while ramping up challenges to China's trade practices and trumpeting the "universal values" of freedom that Beijing, as a developing country, would like to exempt itself from. For advocates of a tougher line on China, the fact that Beijing overplayed its hand reinforced their argument that economic engagement has not delivered the once-hoped-for progress on other fronts. Aaron Friedberg, a Princeton academic, whose book A Contest for Supremacy: China, America, and the Struggle for Mastery in Asia sees the relationship in starkly oppositional terms, is among those who would keep diplomatic niceties to a minimum. "The Chinese have done us an enormous favour, strategically, in the last few years," he said in an interview with The Daily Telegraph this week. Their behaviour has scared everybody and has shaken things up in this country too. It's made people take more seriously the challenge that China poses. The extent of that "challenge" is the unanswered question that looms over this week's visit. Superficially, Mr Xi is a much more approachable figure than his predecessor, the expressionless Hu Jintao, who, according to one Beijing-based diplomat, rode in a car with a (Mandarin-speaking) European ambassador for 40 minutes without uttering a single word. By contrast, Mr Xi has made it known that he is fond of NBA basketball, likes to watch Hollywood movies and - as several residents of the Iowa town of Muscatine, where he spent three days in 1985, have testified - appears to have a genuine affection for America, which has been reflected in some of the unforced bonhomie between him and Mr Biden. Strip away the pleasantries, however, and you quickly arrive at a bedrock of hard differences and strategic conficts that are not currently being bridged by talking. As the dissident Yu Jie confirmed in an interview with this newspaper this week, China remains a country where the secret police can throw a bag over your head, break your fingers and beat you unconscious for writing a book criticising senior leaders such as Mr Xi. On the surface China might increasingly resemble America, with its glittering skylines and six-lane highways filled with GM cars, but after three decades of economic engagement with the West there remain far too many dark corners of the Chinese state. Meanwhile, China's military build-up, still a long way from matching the US, continues apace, with figures this week showing that next year China will spend more on its armed forces than all other Asia-Pacific nations put together. Strategically, China continues to hedge its bets, soft-pedalling on Iran and washing its hands of the bloodshed in Syria by calling it "essentially an internal affair." With such deep, evident differences, Mr Xi has this week urged a longer view, framing what he calls the "drifting clouds" and "temporary disturbances" of the current turbulent relationship against the undeniable achievements in the 40 years since Nixon's landmark visit to China. But as he knows, maintaining the trajectory of those achievements is not a foregone conclusion. The economic dynamic that served both sides over four decades is shifting; the pool of cheap, non-unionised labour that enriched many Western corporations will start to contract from 2015, while technological advances in China's own industrial base, obtained by means fair and foul, are now cutting across the bows of those same corporations. At the same time, China's socially networked middle classes are outgrowing the authoritarian political model that Mr Xi is pledged to perpetuate. China's response is to plead for time and understanding, but as its new leader begins a decade in power, he will find those in short supply, both at home and abroad. One senior Party official in Beijing likened China's situation today to their 7ft 6in basketball star Yao Ming, who was often mistaken for an adult when he was a teenager. China, she argued, might look like a developed nation, but really needed to be treated gently when it came to human rights, trade and global responsibilities. The analogy was more apposite than the mandarin perhaps realised. China is just like a teenager, one minute angrily demanding equality and mutual respect but too often, when asked to meet its responsibilities, begging for a free pass. The world must hope that China turns out OK in the end, but as Mr Obama hinted in his remarks this week, that won't happen unless the West lays down some ground rules and, more importantly, sticks to them.