Both South Korea and the United States need to exercise flexibility and to conduct engagement with the North to cope with current challenges.

On March 26, the Cheonan, a South Korean warship, sank near the Northern Limit Line (NLL). The Joint Civilian-Military Group, which included international experts, was formed to investigate the sinking, ultimately concluding, on May 20, that North Korea was the culprit. On May 24, South Korean President Lee Myung-bak delivered his address to the nation at the War Memorial of Korea, definitively blaming the sinking on the North.

The NLL was established to delimit each maritime area in the West Sea within which South and North Korea would control their respective military forces following the end of the Korean War in 1953. The line was unilaterally set by the Commander-in-Chief of the United Nations force, and has never been legally recognized by North Korea.

Cheonan (Lee Jae-Won/Reuters)

The Cheonan (Lee Jae-Won/Reuters)

The line’s viability has been challenged by three naval clashes between the two Koreas. The most recent evidence of its demise has come with the sinking of the Cheonan, allegedly perpetrated by North Korea.

With regard to the NLL, the harsh truth is that its existence has been mired in near total uncertainty for a long time due to legal neglect and political silence.

The Korean Armistice Agreement, which was concluded by the Commander-in-Chief of the UN force, the Supreme Commander of the Korean People’s Army, and the Commander of the Chinese People’s volunteers in 1953, does not specifically refer to the NLL. The same can be said of the Inter-Korean Basic Agreement, signed in 1991 by the two Koreas. The NLL, therefore, is generally recognized as a self-imposed limitation line determined by the military commander of the United States out of strategic considerations, while lacking a legal basis.[1]

On the other hand, the military demarcation line set by the Armistice Agreement remained a nearly de facto border, which was difficult to enforce legally, as North Korea and China withdrew from the Military Armistice Commission one month after South Korea joined the Commission in 1991.

It was set by the “line of contact” that reflects the confrontation line between the adversaries’ military forces. This is the principle of uti possidetis, which reflects the post-war situation, in contrast to the status quo ante bellum principle that recognizes the pre-war reality.[2] The NLL was created because North Korea accepted the line as a necessity for the cease-fire at that time.

The remaining legal instrument is the Inter-Korean Basic Agreement. Article 11 of the agreement prescribes that both South and North Korea respect the demarcation line provided in the Military Armistice Agreement and the jurisdictions over which each has exercised its authority. However, although this agreement was crafted through the two Koreas’ treaty-making powers, it was not the parties’ intention to subject the agreement to the rule of international law.[3] Thus, it is a non-binding treaty.[4]

Because the Inter-Korean Basic Agreement has no compelling legal force and the effectiveness of the Armistice Agreement has been cast into doubt, it follows that the NLL has been sustained only by necessity of a continuous cease-fire, not by any degree of legal obligation.

Under these circumstances, three maritime wars have broken out between the two Koreas before 2010: the first in 1999 and the second in 2002. The first two naval clashes occurred as the South Korean Navy warned and took action against the North’s warships that crossed over the NLL while escorting their fishing boats. The North claimed that it was the South Korean warships that had invaded the North’s territory. The third conflict occurred in 2009 as South Korea opened a warning fire against the North’s warship that had crossed over the NLL.

In an effort to address this situation, former President of South Korea Roh Moo-hyun and Kim Jong-il, leader of the Democratic People’s Republic of Korea (DPRK), signed the Declaration on the Advancement of South-North Korean Relations, Peace and Prosperity (10. 4 Declaration) on October 4, 2007. The 10.4 Declaration conceives of creating a “Special Peace and Cooperation Zone” in the West Sea with a view to establishing a “joint fishing zone” and a “maritime peace zone” (Section 5).[5] The declaration would place the NLL under control and would prevent further troubles in the West Sea if each side consistently adhered to the agreement.

On the other hand, the policy of Lee Myung-bak, South Korea’s current president, lies in stark contrast to his predecessor. Lee has persisted with an isolationist approach.

In the event of the sinking of the Cheonan, Lee’s government was quick to move toward internationalizing the inquiry into the case, which traditionally would have been recognized as an inter-Korean matter.[6] This move easily aroused international reaction[7] as  a UN Security Council punishment was sought.

Although this move estranged North Korea, it also backfired due to lack of conclusive evidence, which brought about serious domestic skepticism regarding the credibility of the “international” investigation.

The fundamental difference between Roh and Lee is that Lee does not give full credit to South Korea as the primary responsible actor that conducts peacemaking on the Korean peninsula. Roh, whose engagement policy is superior to Lee’s isolationist approach because it would pave the way to renewing the nonviable regime by a peace proposal, showed the way forward. Roh’s approach also could have reinforced the validity of the Inter-Korean Basic Agreement. These moves would secure certainty, evading unnecessary conflicts between the two Koreas.

The forceful push for denuclearization, on the other hand, will not work. The nuclear non-proliferation regime has not been effective in terms of preventing some countries, such as North Korea and the United States, from threatening the use of nuclear weapons in their international relations. Furthermore, North Korea remains outside the regime following its controversial withdrawal from the Nuclear Non-Proliferation Treaty of 1994. Although it is highly unlikely that the North will renounce its last resort for self-defense, pressing for “irreversible” denuclearization, as U.S. Secretary of State Hillary Clinton announced during her recent visit to South Korea, will gain nothing.

Lee’s isolationist approach is not the right way to manage the uncertainty surrounding the NLL and inter-Korean relations. Irrespective of where the truth lies concerning the real perpetrator of the Cheonan sinking, Lee’s reckless internationalization of the investigation into the case will not do anything more than heighten tensions. This is also an unwelcome outcome for the Korean people.

Lee’s government should play a constructive role in creating peace, for instance, by building a special peace zone in the West Sea or establishing an inter-Korean commission to settle issues with the North. Then, both Koreas should focus their efforts on opening the third summit meeting and, renewing their partnership for peacemaking.

The US may be skeptical regarding the six-party negotiations, and it may be tempted to push the North further into denuclearizing. The US has just begun its joint military exercises with South Korea as a warning signal to the North regarding the Cheonan sinking. Secretary of State Hillary Clinton announced the US plan to add new sanctions on North Korea, targeting the North’s arms and luxury goods business, which it hopes will coerce denuclearization.

The United States, rather than joining Lee in his imprudent isolationist action, should secure the room necessary for the two Koreas to exercise bilateral flexibility and restrain the rising tension. This will allow the six-party framework to function continuously toward its aim of denuclearization while helping the two Koreas work out their disputes.

Military incidents or crises do not always require a retaliatory response. And it is worth considering what should have been done in order to begin repairing the situation. This should not be a heavy burden for South Korea and the United States, who should pursue peace over destruction.


[1] Ryeo Hae Institute, Consideration of the Northern Limit Line, (February, 2009)

[2] Ibid.

[3] Ibid.

[4] Ibid.

[5] Ibid.

[6]Scott Snyder, The Cheonan Reckoning: Implications for Northeast Asian Stability, (June, 2010),

[7] Ibid.