By proclaiming a “state of war” with South Korea and the US, Kim Jong-Un is reminding the world about this unresolved problem inherited from the Cold War era.

At the beginning of every spring, Northeast Asia is marked by resumed tensions between North and South Korea. Naval clashes in disputed waters, skirmishing across the Demilitarized Zone (DMZ), military drills and strong-worded rhetoric are hardly novel.

Nevertheless, this year we are witnessing inter-Korean tensions reaching unprecedented heights. Something that looked like a seasonal aggravation of a slow-motion war now threatens to slip out of control and become a full-scale war between the two halves of the divided peninsula.

The Korean War, which started in June 1950 as a war to unify Korea, was effectively turned by the UN into an international conflict, where a coalition of sixteen countries, led by the United States, fought North Korea and China.

Miraculously the conflict did not explode into World War III where the use of nuclear weapons would have been almost certain. Resulting in a stalemate and fragile truce, the Korean War left behind the two irreconcilable regimes – with capitals in Pyongyang and Seoul – frustrated and increasingly adamant to resume the war and accomplish national unification.

Compromise and reconciliation were not in the two Koreas’ political vocabulary until the early 1970s, when the post-war economic development of North and South Korea became comparable. This was when the International Red Cross organization helped separated families from the North and South meet for the first time since the fratricidal conflict.

In 1974 Pyongyang approached Washington with a proposal for a peace treaty; the North Koreans also approached Seoul with a comprehensive plan for peaceful unification. However, the continuing ideological and economic competition of the Cold War in the region precluded the restoration of peace.

Since then the Republic of Korea (South Korea) and the US have staged biannual joint military drills, which take place in the West (Yellow) Sea, south of the DMZ, and in the East Sea (Sea of Japan). During these drills, the allies deploy new types of weapons and tactics, including a simulated nuclear strike. Since the collapse of the Communist Bloc, the Democratic People’s Republic of Korea (North Korea) has developed its own nuclear and missile programs.

But neither of these preparations have helped resolve the persisting security dilemma. Seoul and Pyongyang continue to see one other as sworn enemies, each waiting for the imminent collapse of the other, providing the opportunity for unification.

Even the temporary détente in relations between North and South, known as the decade of the “Sunshine Policy” (1998-2007), did not fully dissipate mistrust and animosity in Korea. Pyongyang continued building its nuclear and missile arsenal, while Seoul continued regular joint military, naval and air drills with its US ally.

As a result, negative inter-dependence has been created in relations between North Korea and US allies in the Asia-Pacific region. North Koreans blame the United States for all its economic misfortunes, while the US and its regional allies, including Australia, always find faults in Pyongyang’s actions and intentions.

The situation of “neither war nor peace” has already led to famine, stagnation, and isolation of this rich and strategically important part of Northeast Asia. By proclaiming a “state of war” with South Korea and the US, Kim Jong-Un is reminding the world about this unresolved problem inherited from the Cold War era.

Leonid Petrov is a Korean Studies Researcher at the Australian National University’s College of Asia and the Pacific. www.leonidpetrov.com