That he would spend nine days away from his domestic agenda and Washington for this four-nation tour shows just how much Asia still means to the US. The region is the most dynamic in the world, contains half of humanity, and yet it bristles with rivalry over resources, territory, and regional dominance.
Mr. Obama will need to deliver a simple message: Tensions must give way to cooperation – and the US will need to be at the table, as it has been for six decades.
As a largely benign benefactor for Asia since World War II, the US can't be excluded from most of the groupings of Asian nations. It still protects the region's sea lanes, keeps its own markets open to Asian imports, and, by its military presence, prevents any of the historic rivalry between China and Japan from erupting again.
This American task has been made easier because the US has the leading military, economy, and currency. But now, with China's Navy on the rise, the dollar slipping in value, and a recession sapping the US role as a voracious importer, the three big Asian nations – namely, China, Japan, and India – see a vacuum of power that one or all of them are trying to fill.
A new Japanese government under Prime Minister Yukio Hatoyama, for example, seeks more independence from its ally and less of a US military footprint on Okinawa. It also proposes an East Asian trade grouping, similar to the European Union – but it's not clear if the US is invited.
Beijing is cool to Tokyo's idea but it is also trying to cement its own ties with neighboring nations – with the US excluded. And it is fast becoming the region's economic superpower while also whittling down the dominance of the US dollar. India, meanwhile, has become closer to the US, but that has only helped trigger anti-India rhetoric from Beijing.
During his tour, Mr. Obama must assure Asia that the US remains a stabilizing force, which is still needed as many nations move toward more open markets, expansion of the rule of law, and the granting of more freedom and rights for their citizens.
The US and Asia have become too intertwined for a rift across the Pacific. As Singapore founder Lee Kuan Yew said recently: "It would [be] a serious mistake for the region to define East Asia in closed or, worse, in racial terms." He added the US cannot continue to be a world leader if it does not keep a strong presence in Asia.
The three giants in the region won't always make it easy for the US to keep a preeminent role. But the more they battle for influence among themselves, the more the US is needed.