Illustration: Andrew Dyson But in 2013 Xi relegated that to history with his new edict. No more waiting. China was now rich. It was time for China to "strive to achieve," said Xi. Ignoring US objections and overriding the claims of China's neighbours, Xi directed the island-building program that has now given China a series of bases in the South China Sea. The region's feeble efforts to resist have failed. Obama's vaunted "Asia pivot" proved irrelevant. Trump has come as a bonus for Xi's ambitions. First it was trade. As Trump tore up the US-led, 12-nation Transpacific Partnership agreement, China's President Xi Jinping declared in pointed contrast: "China will not shut the door to the outside world but will open it even wider." China already dominates world trade by its sheer scale; its work on new regional and bilateral deals will make it an active rule-maker, as well. "The gravity of power in East Asia's regional [trade] architecture appears to be tilting towards the centre, especially in view of China's rise," says a scholar at the Economic Research Institute for ASEAN and East Asia in Jakarta, Ponciano Intal.

Happier times. US President Donald Trump and Chinese President Xi Jinping in Florida in April. Credit:AP Then it was climate change. Trump ranted that climate change was a "Chinese conspiracy". When he signed an executive order in March undoing much of Obama's work to cut carbon emissions, Trump opened the way for China to lead. Beijing, the world's biggest carbon emitter, didn't have to do much to look like a leader. It recommitted itself to its Paris agreement undertakings. But China is also investing more in renewable energy than any other nation, $US88 billion last year, as it strives for global dominance of the sector. And this year it plans to create the world's biggest emissions trading system. "The world is looking for a climate champion," said Nicholas Stern, the famous British climate economist and co-chair of the Global Commission on the Economy and Climate. "In China, it has one," he concluded. Then there was North Korea. Trump specifically asked Beijing to take the lead in crafting a plan to curb North Korea's relentless nuclear missile program. After realising there are no easy options on this problem, Trump announced Xi is "a very good man" and that "I believe he is trying hard" to solve the problem in Pyongyang.

This isn't necessarily an assignment that Beijing would have relished. But it is an implicit acknowledgement that the Korean peninsula is part of China's sphere of influence and a concession that US diplomacy is exhausted. Finally there is China's "Belt and Road" plan. Xi opened a meeting in Beijing on Sunday to discuss the proposal, with 100 countries including 28 heads of state in attendance. He declared this vast visionary infrastructure concept as "the project of the century".

The plan has a "belt" running across land and a "road" running across the seas. On land, Beijing aims to connect China's hinterland to Europe through Central Asia. This route has been dubbed the Silk Road Economic Belt. On water, a 21st Century Maritime Silk Road is proposed to connect Southeast Asia to southern China through a system of ports and railways. Sixty-five countries have formally signed up as participants, with many others, including Australia, circling on the periphery. As conceived by Xi, this will be far bigger than the US Marshall Plan for the postwar rebuilding of Europe, adjusting for inflation. Estimates of the ultimate scale of investment range from $US1 trillion to $US4 trillion and beyond. If realised, it could be the biggest international infrastructure program since the Roman Empire. To date, China has committed about $US100 billion.

The leaders in attendance weren't just tinpot supplicants. They included Indonesia's Joko Widodo, Turkey's Recep Erdogan and Russia's Vladimir Putin. Even the US sent an official, the White House director for East Asia, in the hope that US companies might pick up some of the business. Of course, the project would be a tremendous flexing of Chinese economic sinews across half the earth. It is a positive platform for Chinese influence into scores of countries. Xi took pains to assure leaders that he was not interested in "outdated geopolitical manoeuvrings" and sought only "win-win" cooperation. Yet we know China has used economic coercion of smaller countries whenever it suited. South Korea and Taiwan, for instance, are suffering undeclared Chinese sanctions right now. And not everyone is happy with the Belt and Road. India opposes it as an intrusion. Japan is very uneasy at the implications.

Nonetheless, is the mantle of global leadership passing to China? Rory Medcalf of the ANU National Security College says it's "too early to call".

A true world leader provides public goods to the international system, even when it comes at some difficulty and expense. The US is allowing its traditional management of some global public goods like trade liberalisation and climate change mitigation to lapse. But China's initiatives to date fail to meet this high standard, argues Medcalf. China is too narrowly nationalistic, he says. "The world is more likely to go through a phase without a clear leader than to go into Chinese leadership," he says. Global leadership, quite suddenly, is up for grabs. China is grasping for the mantle and it's not yet clear that it can win it. Can the US recover it? Or is history leaving Trump's America behind? Peter Hartcher is international editor.