A week is a long time in the calendar of an American president, but a short period in which to repair the perception that the world’s dominant power has lost interest in the world’s most dynamic region. Asia requires closer American attention, and a more imaginative approach than has been seen in Washington since the volte-face on China of the Nixon-Kissinger years.

As George W. Bush noted at the start of his week-long visit, “a modern and confident Asia” has been carefully nurtured by the United States for the past 60 years. The importance of this Pacific relationship goes beyond trade and investment, or such immediate strategic imperatives as dealing with North Korea. As China heads towards third place, behind Japan, in the global economic ranking, the question of how that power is used will dominate thinking in the mid-21st century.

Asia contains a third of the world’s population, generates half its wealth and is destined to play a still larger role once India consolidates its emergence in the global marketplace. Its economies are more integrated and more energetic than those of Europe. The same, however, cannot be said of Asia’s management of the political dimensions of interdependence.

Regional co-operation has been stunted by old grievances and Cold War faultlines and by the enduring inability of China and Japan, in particular, to close the bitter chapters of their recent history. Asia has no effective regional security organisations — or coherent economic groupings.

South-East Asia’s Asean group cannot even bring Burma to account and although Apec, the 21-nation Asia-Pacific Economic Co-operation forum whose summit Mr Bush attends today in Hanoi, has existed for 17 years, Asian governments characteristically shrink from converting it into a fully fledged economic organisation.

The US will be well pleased if Mr Bush obtains strong Apec support for UN sanctions against North Korea, and signs that there will be renewed vigour in the Doha Round global trade talks. But, as the US must by now have learnt from long experience, however useful such large Asian forums may be for broad restatements of America’s friendship and for brief one-on-one bilateral encounters, they are not occasions where much business is done.

Asia will pull together politically only when relations between its two most important players, China and Japan, improve; and they are unlikely to improve significantly without active US involvement. China’s apparent readiness to do business with Japan’s new Prime Minister, Shinzo Abe, is an opportunity to convert a limited bilateral thaw into a solid three-way working partnership. Mr Bush should invite Mr Abe and President Hu Jintao of China to a more intimate summit, with the explicit aim of making such meetings regular events in their schedules.

Without detracting from the US-Japan alliance, collaboration between these great powers could do much to improve Asian stability, manage climate change and protect the global economy from future shocks. China has indicated that it would be keen to attend such a meeting — all that it needs from Mr Bush is a firm invitation. There will doubtless be endless debate about which is the most important bilateral relationship in the world. There should be absolutely no doubt that the most important trilateral relationship, economically and politically, is that of the US, China and Japan.