CHINA'S decision to declare a maritime air defence zone over disputed waters in the East China Sea late last month, together with the more recent response of Japan and South Korea, is both alarming and rather surprising.
This is, after all, a region that has been essentially conflict-free for decades, despite containing some of the world's most seemingly combustible flashpoints and deep-seated rivalries. The sudden deterioration in the security environment is shattering some of our most fundamental assumptions about the basis of regional security.
To get a sense of how important and unexpected all this is, it is helpful to place these events in historical context. The institutional architecture that has kept the region remarkably stable for decades was established in the aftermath of World War II. True, there were major wars in Vietnam and Korea, but within the non-communist camp, at least, peace prevailed.
One of the key reasons the so-called "capitalist peace" endured was not that making money proved more attractive than making war, but rather because the grand bargain was actually imposed. Despite not being part of the region, the US enjoyed an unprecedented dominance in East Asia and effectively determined the post-war regional order.
Two aspects of the East Asian region at this time were crucial.
First, although one tends to think of the Cold War as largely being about the containment of communism, it is important to remember that in East Asia it was also about containing Japan.
The US had a particular interest in ensuring that Japanese militarism was eradicated. Japan's so-called "peace Constitution" and the subsequent focus on economic development ensured this happened.
While China's economic rise seizes the attention of the world these days, it is important to remember that it was Japan that pioneered Asian-style, state-led economic development. It was also Japan that became the cornerstone of the entire economic and strategic order that allowed the region to take off in a way that astounded the world.
The second critical aspect of the post-war order was the series of formal strategic alliances between the US and key regional states like Japan, the Philippines and Australia. Not only did these relationships underpin the security of the region, but they effectively marginalised those countries that were not part of the capitalist camp. China's economic expansion really gathered pace after the Cold War ended, when economic integration became a truly regional business.
These events are not merely historical curiosities.
On the contrary, the unravelling of this longstanding regional order is at the centre of the current rising tensions. Not only are a number of countries still carrying a good deal of historical baggage from this period in the form of lingering animosities and unresolved territorial claims, but the very foundations of the old order are coming apart.
Paradoxically enough, the creation of the conditions in which East Asia could prosper has also created formidable competitors for the US, as first Japan and now China challenge and undermine its economic pre-eminence.
The basis of American power and independence of action is being eroded as it becomes increasingly reliant on the East Asian region to underwrite its rapidly deteriorating fiscal position.
The transformation of the region's economic order is also having an impact on the security situation.
The most visible manifestation of this possibility is China's growing military capability and its more assertive foreign policy. While China may understandably have become the primary focus of attention in a region still nervous about the Middle Kingdom's re-emergence as the most powerful economic and strategic force in East Asia, Japan remains a potentially pivotal actor, too.
Despite the recent "rebalancing" towards East Asia, the US has long urged Japan to do more "burden sharing" when it comes to underwriting regional security. It may finally be getting its wish as politically born-again Premier Shinzo Abe tries to make Japan a "normal" country.
Yet, urging Japan to abandon its rather admirable antipathy to war was arguably not wise at the best of times. At a time when the chances of accidental or intentional conflict with its old foe cannot be discounted, it looks foolhardy.
The risk for the US and the rest of the region is that the very strategic architecture that seemed to provide certainty for so long may now become a source of great danger. On his recent trip to the region, US Vice-President Joe Biden was at pains to assure friend and potential foe alike that America would honour its security agreement with Japan and defend it in any conflict with China. It is not impossible that this pledge may be put to the test. If the US fails to act on Japan's behalf, its credibility as an alliance partner and security guarantor will be destroyed.
We can only hope that such fears are groundless and fanciful.
But as many observers have pointed out, much the same was said about European powers before World War I, when growing economic interdependence seemed to make war unthinkable.
Tragically, however, a series of alliance relationships was triggered by the entirely random, unexpected assassination of Archduke Franz Ferdinand. The rest, as they say, is history.
It is not impossible the world faces a similar dilemma. It is safe to assume that nobody in Beijing, Tokyo or Washington thinks that a major inter-state conflict is a good idea, much less "winnable".
And yet, they risk being sucked into a European-style catastrophe by accident or miscalculation.
Alliances are valuable as long as they deter risky or expansionist behaviour. When they fail to do so, they may actually make conflicts significantly worse. The best hope for long-term stability in East Asia is one in which regional powers play a bigger part.
Japan and China must not only settle their own differences, they must also cooperate to underwrite regional security.
The Asean Regional Forum provides a ready-made, albeit underutilised and underperforming potential vehicle in which joint leadership could be exercised. While this may look an unlikely prospect at present, history reminds us of the importance of making the effort.
The writer is professor of international politics at Australia's Murdoch University