Practically speaking, there are limits to what disaster relief Asean could possibly lend. Japan is by far better resourced and Asean members still struggle to meet their own needs. But the meeting is significant for future policy.

The most immediate of these will be for energy. Four Asean countries - Vietnam, Thailand, Malaysia and Indonesia - have plans to develop nuclear plants while Singapore is undertaking a study to better understand the technological choices, costs and risks.

Some countries - Indonesia and Thailand - are exposed like Japan to the risks of earthquakes and tsunamis. No Asean member currently has nuclear power plants and must turn to foreign expertise, including Japanese energy companies, if they move ahead. What has happened at Fukushima must therefore be closely studied.

At the meeting, Japan agreed to increase its transparency and communication of the still unfolding situation. Subsequent news that the incident is now comparable to the worst ever nuclear incident, Chernobyl, only heightens this need for ongoing and candid assessment.

A second energy concern that is emerging is the need for alternatives. It is likely that imports of gas will surge in Japan and long-term contracts will probably be pursued from Indonesia and others.

A third policy implication will be for industrial production. In the months before the earthquake, leading Japanese companies were looking to expand their manufacturing operations in Southeast Asia. This was originally to deal with higher costs in Japan, from the strong yen, and to diversify from production in China.

These reasons remain. Indeed, the need is compounded by the energy shortages looming domestically. The outward push by major Japanese companies should therefore be expected to continue, although its initial pace must be managed to ensure jobs are not lost in affected provinces, further affecting their economy.

Overseas expansion will help with another knock-on effect - the impact on the global supply chain when some production halted in Japan. Given this phenomenon, Japanese manufacturing operations in the region will look to further indigenise production with higher value-added components and products. By so doing, manufacturing in Southeast Asia - beyond cheaper land and labour - can help Japanese companies minimise potential future disruption to their global production.

Political engagement in the wake of the tragedy is also critical. Some have tended to look past Japan to a rising China in recent years. But this is not and never should have been an 'either/or' choice.

Japan's participation in Asian regionalism has many dimensions that are different and indeed complementary to a rising China. Without involvement and commitment from Japan, the still emerging institutions for the region will be weaker or otherwise move in directions that may not be fully comfortable for some Asian governments.

Some hope the Kan government will gain support in the wake of the tragedy as society rallies round, and Japan can show consistent leadership. But even if this does not happen, reaching out to Japan will be fundamental to Asean's goal to serve as a hub for the wider Asia.

Japan remains important and indeed is integrated in Asia as 'one of us'. This was the case before the earthquake and remains so. This is so not only in politics and industry, but also in the consciousness of everyday citizens across the region. Sadly, it has taken this disaster to remind more people of this.

Simon Tay is chairman of the Singapore Institute of International Affairs