White House officials and Washington pundits welcomed the move by Japan to reinterpret its 60-year-old pacifist Constitution, even as they stressed the need for Tokyo to be transparent with its neighbours in how it implements the policy.
And while US administration officials left vague just what sort of military contributions it expects from its Japanese allies, experts said any potential defence cooperation will be limited, given the sensitivities in the region and among large sections of the Japanese public.
On Tuesday, Japanese Prime Minister Shinzo Abe announced a decision by the government to allow its armed forces to aid friendly countries under attack and not just act in self-defence.
The move sparked strong reactions from Japan's neighbours China and South Korea, but Washington expressed support for a less inhibited Japanese army.
Deputy National Security Adviser for Strategic Communications Ben Rhodes told foreign journalists in Washington that the US "very much welcomes" the move, noting that President Barack Obama discussed the matter with Abe during a visit to Tokyo in April.
"We believe it's part of the continued maturation of our alliance and it opens the door to additional cooperation.
"When you look at issues such as Japan's support for peacekeeping efforts around the world or their commitment to regional security and stability in Asia, I think this policy creates space for Japan to play an even greater role as a security partner of the United States and as a country that upholds international order," he said, echoing sentiments from State Department officials.
He downplayed the likelihood of the move raising tensions at a time when distrust between countries in the region is at a high.
"If it (the Japanese collective self-defence policy) is pursued in a transparent fashion in consultation with neighbours in the region, that can reduce misunderstanding and tensions," he said.
Shihoko Goto, North-east Asia associate for the Wilson Centre's Asia programme in Washington, similarly said that Japan needs to move forward carefully to avoid raising tensions.
"For the Abe administration, building trust with neighbouring South Korea and eliminating any misunderstandings about what exactly collective self-defence will mean is crucial," she said.
The one largely unanswered question, though, is what the US will want Japan's Self-Defence Forces to do that they are not already doing.
Rhodes would say only that the issue was still being assessed.
Foreign affairs experts told The Straits Times that the options for military-to-military cooperation would be limited.
Japan has made it clear it will not be getting involved in conflicts in Iraq and Syria.
Adding to the restraint is the role played by the New Komeito party, the ruling Liberal Democratic Party's junior coalition partner.
"The (New) Komeito insists that any further expansion in Japan's decision to allow the Self-Defence Forces to use force will require a formal process of constitutional revision that includes a national referendum that allows the Japanese people to have a direct voice in the decision," said Dr Sheila Smith, senior fellow for Japan studies at the Council on Foreign Relations.
Jeremy Au Yong
Business & Investment Opportunities
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