When the five foreign ministers of Indonesia, Malaysia, the Philippines, Singapore and Thailand came together to will Asean into existence on Aug 8, 1967, squabbles between the young South-east Asian countries were a fresh memory.
Ties between Malaysia and the Philippines were strained by territorial disputes over Sabah, while Indonesia had just wound down its violent campaign of Confrontation against Malaysia and Singapore.
Nationalism was on the rise, and the idea of a collective South-east Asian identity seemed a hopeless ideal. But Asean surprised the doubters, and overcame internal antagonisms to enjoy more than four decades of solidarity.
However, in recent years territorial disputes - this time involving China, over the South China Sea - have consumed much of the grouping's attention.
Such are the challenges faced by the Asean Political-Security Community (APSC) and the Asean Socio-Cultural Community (ASCC), two of the three pillars of the Asean Community. The other, of course, is the Asean Economic Community (AEC).
ASEAN POLITICAL-SECURITY COMMUNITY
We all grow up taking it for granted that we have no war in our region, but it requires a lot of effort among government leaders, among senior officials in Asean governments to work together to maintain peace and security.
DR TERMSAK CHALERMPALANUPAP, visiting research fellow at Iseas-Yusof Ishak Institute, on the absence of wars and brinkmanship among Asean members
The APSC deals with transnational security issues such as crime, defence and law, and is the mechanism under which the foreign, law and defence ministers of each country meet regularly.
Until the South China Sea tensions ruffled Asean's fabric, solidarity among member states has served the region well: there have been no wars or brinkmanship among members since its formation, allowing economic activity to flourish, notes Dr Termsak Chalermpalanupap, a visiting research fellow at Iseas-Yusof Ishak Institute.
"We all grow up taking it for granted that we have no war in our region, but it requires a lot of effort among government leaders, among senior officials in Asean governments, to work together to maintain peace and security," he says, adding that the region is a nuclear-free zone because members have collectively willed it.
The bloc's reputation for being neutral, constructive and non-ideological has also given it what Dr Termsak calls "convening power": the influence and ability to attract dialogue partners even from far afield.
"When Asean calls for a meeting, many countries outside our region come and join us, they all want to work with us," he says.
"Even North Korea is interested in Asean: this is the only place outside of the United Nations system that (it) has anything to do with other countries in a peaceful way."
But the South China Sea disputes and a willingness by China and the US to assert their influence over individual Asean members threaten to undo Asean's solidarity.
China's "One Belt, One Road" developmental initiative, launching of the Asian Infrastructure Investment Bank (AIIB) and launching a forum to rival the Singapore-based Shangri-La Dialogue all point to a multi-pronged approach to rebalance the US-dominant world order, says S. Rajaratnam School of International Studies senior fellow Yang Razali Kassim.
"While moves such as 'One Belt, One Road' and the AIIB have won it new support, China has succeeded in equal measure to antagonise and generate distrust in the region because of its unsettling and divisive impact, especially on Asean," he said in a recent article.
"There is growing uncertainty over the ultimate motive of China's push to revive the Silk Road in South-east Asia: whether it is really to cooperate for mutual gain, or to undermine established relationships in the region."
Member states have their work cut out if they wish to maintain Asean centrality, or the principle that the grouping should be in control of key decisions affecting the region.
Prime Minister Lee Hsien Loong alluded to the challenges Asean faces in this area at the close of last year's summit in Myanmar.
"Centrality is not something which you can declare and claim. It's something which you have to earn from your relevance, from your effectiveness, from your cohesiveness," said Mr Lee.
"The more Asean can play that role, the more other countries find us useful, the more we can say that Asean centrality is a reality."
ASEAN SOCIO-CULTURAL COMMUNITY
Broadly speaking, the ASCC deals with issues that directly affect the populations of member countries that are not purely economic in nature, such as in education, youth, health, disaster management and poverty eradication.
"When you say socio-cultural, the first thing that comes to mind is something to do with song and dance," says Ms Moe Thuzar, a lead researcher at the Asean Studies Centre of the Iseas-Yusof Ishak Institute. "But it's not about song and dance: it's really about responding to the effects of what happens in the political areas, or what happens due to economic integration."
The ASCC is also the part of Asean that works towards closing developmental gaps between most and least advanced members.
Launched in 2000, the Initiative for Asean Integration is a working group of representatives of all members who have the task of closing developmental gaps between Asean countries and accelerating the economic growth of new members such as Cambodia, Laos, Myanmar and Vietnam.
It is also how countries like Singapore, Malaysia and Thailand share their expertise and technical know-how with newer members, says Ms Thuzar.
But while the ASCC has seen some successes - creating mechanisms that bring ministers and officials together to work on topics such as women and children's issues and disaster management and emergency response - much still hinges on each country's implementation.
The haze that recently blanketed the region because of hot spots in Sumatra and Kalimantan demonstrates this, says Ms Thuzar. "We are seeing the effects of weak national implementation in the haze that has spread across borders."
ASEAN ECONOMIC COMMUNITY'S ROLE
Amid emerging tensions in Asean's geopolitical space, one aspect of the AEC is a practical incentive for members to stick together - by growing incomes and overall prosperity through forging relationships across countries.
"The idea for the AEC was born partly from recognition that deeper integration would support economic growth," says the Economist Intelligence Unit in a special report on Asean.
"Equally, it was forged against the rise of China and India: national leaders in South-east Asia hoped that, by joining together, Asean could become a formidable third economic engine in emerging Asia."
Members are near the finish line in negotiating a final agreement on the liberalisation of the service sector and have committed to implementing the Asean open skies agreements, which will open up competition in the regional air travel market.
Technologies based around the mobile Internet - such as the growth of e-commerce from one of the most smartphone-saturated areas of the world - will potentially account for between US$220 billion (S$310 billion) and US$625 billion in the region by 2030, according to a McKinsey Global Institute report.
This means members are likely to push harder for a South-east Asia-wide free mobile roaming zone that will eliminate mobile phone roaming fees within Asean.
First mooted in 2012 by Indonesia's then Communication and Information Minister Tifatul Sembiring, the idea may see greater impetus now that the European Union announced last month it will eliminate mobile roaming charges within the EU.
In a sign of greater momentum in this area, an agreement between Brunei and Singapore to reduce roaming rates for travellers between the two countries came into effect this year. This adds to a similar agreement that Singapore signed with Malaysia in 2011.
To get an idea of the significance for the region of free roaming, consider this: If Asean were a country, while only one of every 10 people would own a telephone line or be an Internet subscriber, there would be more than one mobile phone per person, many with data connections.
These statistics on phone users were presented last month at a community forum, titled "Impact of Asean Integration", organised by Minister in the Prime Minister's Office Chan Chun Sing and Buona Vista Community Club. They are just one of several sets of statistics given that night to explain the importance of the grouping.
Indeed, free roaming is just one of the bright spots that Asean's young, mobile phone-loving populace can look forward to under its three-pillared community.