Indian Ocean storm buffets US-Japan alliance
The two Japanese ships steaming home from the Indian Ocean today, their mission to support US-led operations in Afghanistan shelved, are sailing into a sea of uncertainty in the wider US-Japanese relationship.
The security alliance at the core of that relationship has for decades been a bedrock Japanese policy, reflecting strategic assumptions that have long governed the region.
The United States' bases in Japan - a presence that includes the only permanent carrier strike group kept outside the country - lie at the core of Washington's position as the leading military power in Asia.
Japan, meanwhile, has long been secure in a dangerous region under the arrangement, keeping a pacifist constitution and spending less than 1 per cent of its gross domestic product on its military.
Yet the wrangle over deploying the ships, part of Japan's Maritime Self-Defence Forces, in the Indian Ocean is exposing deeper cracks in the US-Japanese relationship.
Diplomats on both sides have acknowledged the existence of tensions - now being closely watched around the region ahead of a flurry of diplomacy in the next few weeks.
On the US side, Washington is eager for new Japanese Prime Minister Yasuo Fukuda to push ahead with legislation to renew the mandate as soon as possible.
It marks an important symbol of Japan moving towards a more 'normal' military footing and promoting the internationalisation of the Afghanistan mission.
Ships from US ally Pakistan, for example, have been among those refuelled by Japanese vessels.
Washington is also keen to address long-simmering issues over its Japanese bases, including greater Japanese payments for water and utilities to help the US meet rising security challenges in East Asia.
Mr Fukuda, meanwhile, is seeking to shore up the traditional relationship even as his Liberal Democratic Party battles attempts by the resurgent opposition Democratic Party of Japan to force an early election over the refuelling issue.
The ships have been forced home by the opposition's refusal to back routine laws extending their mandate in the Indian Ocean. It insists the ships should leave Japan only at the request of the UN.
Mr Fukuda's party could still push through a bill using an override in the lower house, but such a move could come at a political price. The Indian Ocean deployment has never been a hit with the public.
Other issues dog Mr Fukuda's cabinet. Many senior Japanese politicians are quietly angry at the rule of US President George W. Bush, particularly the quagmire in Iraq.
Then there is resentment over their shared enemy, North Korea, and a sense that Japan has been kept on the sidelines at crucial moments in efforts to forge an era of peace with Kim Jong-il's hermit regime.
Some analysts also believe senior LDP figures are getting jumpy at the prospect of a US presidential election victory by Democratic frontrunner Senator Hillary Rodham Clinton, fearing she would put a premium on relations with China.
'There are some difficulties right now and there is plenty to talk about in the weeks ahead,' a Japanese official said. 'But that is the same for any long and close relationship ... US relations, of course, remain a priority.'
US Defence Secretary Robert Gates is expected to visit Tokyo late next week for discussions with Mr Fukuda's cabinet over the range of issues now confronting the alliance.
Mr Fukuda, too, is expected to visit Washington soon in his first trip to the US capital since taking office following the sudden resignation of Shinzo Abe in September.
A more moderate conservative than the blue-blooded Mr Abe, Mr Fukuda has placed great stock in continuing the solid US relationship while reaching out to the region, particularly to China, which is now Japan's biggest trading partner.
His opposition is making sure it is a complicated juggling act.