The abrupt shift in US policy toward the ailing Japanese yen underlines the growing and influential role China is playing in global affairs and a possible shift in Asia's balance of power.
The joint intervention by the United States and Japan Wednesday to bolster the yen raises many questions, not least why the US administration, after weeks of saying the yen was Japan's problem, abruptly changed its mind.
One theory involves China. In recent days, comments from Chinese officials raised the unnerving prospect of a possible devaluation of China's currency, the yuan, something the government had repeatedly said was not on the table.
In a Reuters interview this week, Sun Zhenyu, vice minister for foreign trade, said if the fall in the yen put pressure on China's exports, the government might consider a change in its policy toward the yuan. Mr. Sun later denied that he was suggesting the possibility of devaluation, but his comments coincided with other official remarks that sought to pressure Japan and the US to stop the yen's slide.
The risk of a yuan devaluation, and what that would mean for the rest of Asia, seems to be very near the center of the Clinton administration's worries.
"The thing that everyone fears the most is the devaluing of the yuan, the Chinese currency," says one US official, speaking on condition of anonymity. "There was a definite feeling that you are risking even more damage to Asian economies and emerging economies all over the world if you let the yen continue to slide."
What is remarkable about this episode, say analysts, is the contrast between Japan, the world's second-largest economy, and China, the world's most populous country and growing economic and political force. The former has demonstrated a lack of strong political leadership in dealing with its problems. China, meanwhile, has quietly emerged as a stable force in the region, coupling its economic prowess with the kind of responsibility befitting a global power.