In case one needed reminding, the latest exchange of fire across the unresolved maritime border between North and South Korea illustrates how precarious Asia's security environment has become. The North is reported to have given warning by fax to the South at around 8am local time and fired around 500 artillery rounds in the early afternoon into seven locations. The South returned fire with around 100 Howitzer rounds and scrambled air force jets to over fly border islands.  All rounds landed in the water.

Thus far the two sides have avoided the fatalities that occurred during the North's 2010 shelling of Yeongpyeong and appears unlikely to result in any significant escalation.

In the first instance, the exchange of fire is part of a broader response to increased US-ROK military interaction. Here it seems likely that the DPRK live-fire exercise is the second of a three-part act. The first was the launching of short range missiles in early March, with the third flagged as a further nuclear test later in the year, quite possibly in May. Given the importance the regime places on acquiring nuclear weapons and its need to conduct further tests to realise this ambition, a further test has come to be expected.

The shelling is also part of a regular process whereby the two Koreas test each other's claims to the maritime boundary. The South's claim is the Northern Limit Line established by the UN in 1953, while the DPRK asserts a more southerly Military Demarcation Line. 

The shelling also has to be seen in the context of the Kim Jong Un's consolidation of power. This sequence of military provocations is the first after the remaining vestiges of Kim Jong-il's regime were removed.

Many had hoped that after concentrating power, Kim Jong Un was going to begin a program of cautious economic reform and adopt a somewhat more moderate international posture. But this exercise seems to indicate that the DPRK is unlikely to change its approach to security in the short term future. Perversely, it is unlikely to moderate its behaviour until it feels the security that it believes nuclear weapons can provide. Only then are we likely to see a shift in approach. Expect more provocations from Pyongyang.