TOKYO - Prime Minister Shinzo Abe's whirlwind tour last week of three Asean capitals - his first overseas trip since taking office - underscores the renewed importance of South-east Asia to Japan.
Japan needs South-east Asian nations, not just to boost its own flagging economy, but also as strategic partners in dealing with a rising China.
Given Mr Abe's priority of revitalising the economy, it is important that Japan is able to tap into Asean's dynamic economic growth, which has intensified demand for Japanese exports and also created a huge demand for better infrastructure.
To that end, the Japanese leader was seen pushing high-speed rail systems in Bangkok. Japan also remains keen to sell nuclear power plants to Vietnam despite the fact that the Fukushima nuclear disaster remains unresolved.
But perhaps the most important message that Mr Abe brought with him was that Japan is anxious to deepen its alliance with Asean nations, not least in coping with the challenge of an increasingly belligerent China in maritime territorial disputes.
In the South China Sea, China lays claim to island clusters that are also claimed by several Asean states.
Farther north in the East China Sea, it is involved in a long-simmering feud with Japan over the ownership of the Senkaku islands, which the Chinese call Diaoyu.
At a press conference in Jakarta, Mr Abe acknowledged that China's rise is "without question" a plus for Japan economically.
But he was also quick to add that it was "important for China to act responsibly in the international community".
As the influential Nikkei business daily pointed out, the biggest common concern binding Japan and the Asean countries is how to engage a rising China.
But it may be difficult to rally the Asean nations together against Beijing, given that some members are likely to flinch at the thought of rankling China, which has become closely linked economically with the region.
It was unfortunate that Mr Abe's Asean swing was overshadowed by the hostage crisis in Algeria.
News that some Japanese were among the hostages reportedly reached the government here about 10 minutes after Mr Abe touched down in Hanoi, his first port of call, last Wednesday.
On Friday, the unfolding crisis cut short his visit to Jakarta, his last destination.
In the Japanese media, news of the hostage crisis almost squeezed out reports of Mr Abe's Asean visit.
Despite having to cancel a key policy speech in Jakarta, Mr Abe managed to use a press conference to spell out the five principles underlying Japanese diplomacy in Asean contained in that address.
These include protecting freedom of expression and other universal values, and the promotion of economic as well as cultural ties with Asean nations.
But perhaps the most important principle that Mr Abe cited is the use of the rule of law to resolve maritime disputes, a veiled reference to China's inclination to resort to the use of military muscle.
But as some Japanese newspapers pointed out, it may not be in the interest of the region for Japan and Asean to be seen as trying to contain China.
Rather, efforts should be made to persuade China that international law is the best means of preserving regional peace.