As no major war has erupted between the North and South, has this invalidated offense-defense theory?

I argue that the absence of a major war between North (DPRK) and South Korea (ROK) does not disprove the offense-defense theory (ODT) because the theory is capable of explaining the prevalence of peace under conditions when the defense has the advantage.

This paper is organised as follows. Firstly, I will offer a definition of the ODT. Following that, I will explore three indicators that account for the dominance of defense on the Korean peninsula and will elaborate on the predictions for peace that the ODT makes as a result of these factors. These are 1) the defensive alliance between the ROK and the United States of America (US), 2) the possession of the nuclear weapons and finally 3) the geographical impediment that is the demilitarized zone (DMZ) dividing the North and the South at the 38^th parallel. Moving on, I will consider how the ODT is a more credible theory to explain the absence of war on the Korean peninsula than neoliberal institutionalism. Finally, I will suggest how the absence of war on the Korean peninsula might be used as an example to propose some refinements to the ODT.

The ODT posits that war is more likely to occur when conquest is easier.[1] The ease of conquest is determined by shifts in the offense-defense balance (ODB) which is ‘an aggregate of military, geographic…and diplomatic factors’[2]. Accordingly, the likelihood of war is increased when the aforementioned factors ‘increase the ease of offensive operations or…significantly reduce the costs of such operations’[3] vis-à-vis the cost of defense against aggression, while the converse holds true. As I will go on to prove, the confluence of diplomatic, military and geographic factors on the Korean peninsula have shifted the ODB towards the dominance of defense, thus accounting for peace.

Defensive alliance

I argue that the ROK-US Mutual Security Treaty which enjoins its signatories to ‘maintain and develop appropriate means to deter armed attack’ by an external party[4] is a key diplomatic factor promoting peace on the Korean peninsula by serving as an effective deterrence against any potential acts of aggression by the North. That it is effective can be judged by three factors: 1) the implementation of a tripwire strategy, 2) the significant number of American troops deployed in South Korea and 3) American political rhetoric that is commensurate with displays of military might in support of the ROK.

The ROK-US mutual security treaty is only as effective as the US commitment to the alliance is judged to be credible by potential aggressors, such as North Korea.[5] To this end, the implementation of a tripwire strategy in South Korea guarantees American commitment to its defense against acts of aggression undertaken by the North, thereby reflecting the effectiveness and credibility of the treaty. Accordingly, the strategic positioning of the majority of American military troops along the most probable invasion routes to Seoul[6] ensures that in the event of an invasion by the North, they will be forced to engage American troops. In turn, this will trigger an automatic US response to aid the defense of South Korea.[7]

The effectiveness of the tripwire strategy is further enhanced when one considers the level of American troop deployment in South Korea and in neighbouring Japan. To date, there are 28 500 American soldiers in South Korea,[8] which includes the Army’s Second Infantry Division and several Air Force tactical squadrons.[9] In addition, there are also 47 000 American soldiers based in Japan which can be swiftly used to supplement those in South Korea in the event of any aggression taken by the North.[10] Thus, it is apparent that the tripwire strategy represents a credible demonstration of American resolve and commitment to the ROK-USA mutual security treaty which North Korea will find hard to underestimate in their calculations for waging war.[11]

American political rhetoric in support of the South has also been backed up by displays of military might in times of provocative behaviour by the North. This congruence in word and deed further underlines the credibility of American commitment to the defensive alliance by demonstrating their willingness to render international support to the South. The aftermath of the sinking of the South Korean warship the Cheonan in March 2010 provides an illuminating example to illustrate this point. Following US President Barack Obama’s condemnation of North Korea’s “irresponsible behaviour” that had to be “held to account”,[12] a joint US-ROK naval exercise codenamed Invincible Spirit was conducted;  according to the US Defense Department, this was a direct response to the sinking of the Cheonan.[13] Thus this incident highlights the congruence of American rhetoric and deed.

Given the credibility and effectiveness of the ROK-US security treaty, the ODT predicts that the high cost of conquest will cause the DPRK to refrain from opportunistic expansion for fear that ‘victory will prove…unattainable’[14]. Thus this prediction contributes to explaining the absence of a major war on the Korean peninsula.

Nuclear weapons as  defense

The absence of war on the Korean peninsula can also be attributed to the possession of nuclear weapons by the USA and the DPRK. This can be examined in terms of 1) the US nuclear umbrella over the South and 2) the development of DPRK nuclear weapons for defence.

Before proceeding, it is necessary to reconcile how nuclear deterrence can increase the advantages of the defense. According to the ODT, nuclear weapons are seen to contribute to the dominance of defense because it becomes relatively cheaper and easier to maintain a defensive force than to build an offensive force. As such, in a Mutually Assured Destruction (MAD) world, nuclear deterrence becomes the ‘functional equivalent of defense’[15] as it threatens to severely punish its attackers.[16] As Kenneth Waltz notes, ‘second-strike nuclear forces serve that kind of strategy (of deterring by punishment).’[17] Hence, I argue that the aforementioned logic of nuclear deterrence contributes to the dominance of defense by threatening aggressor states with punitive punishments, thereby increasing the cost of war and making peace more likely.

Although nuclear weapons were removed from South Korea in 1991, nuclear deterrence continues to hold over the country largely as a result of the US nuclear umbrella, which is a function of the ROK-US security treaty. Under the logic of the nuclear umbrella, any nuclear strike by the North on South Korea will be perceived as a hostile act against the US themselves and will trigger an immediate US nuclear backlash.[18] Accordingly, the US continues to maintain a formidable stockpile of nuclear weapons in the Pacific region that can be used to implement the nuclear umbrella over South Korea should the need arises.[19] American political rhetoric also continues to allude to the existence of the nuclear umbrella over South Korea. For instance in 2009, American President Barack Obama reiterated the commitment of the US nuclear umbrella to his South Korean counterpart President Lee Myung-Bak during an ROK-US summit meeting; this came shortly after North Korea’s nuclear test one month earlier.[20] Thus, nuclear deterrence holds sway over the South as a result of the US nuclear umbrella.

Concurrently, I argue that the nuclear arsenal of the DRPK also functions as deterrence against any potential aggression by the South and their American allies. That the North’s nuclear stockpiles serves a defensive purpose can be deduced from the conditions they attached to an agreement that allowed international inspections of their nuclear facilities.[21] Under these conditions, the North agreed to the inspection only if they were assured that ‘they were under no threat of nuclear attack from some other country.’[22] This alludes to the security dilemma that the North finds themselves in vis-à-vis the ROK-US security treaty and the concomitant nuclear umbrella. Consequently, one can deduce that their nuclear programme has developed out of a ‘perceived necessity’ to safeguard their own security. Further evidence to prove that the North’s nuclear programme serves a defensive function can be inferred from their continued emphasis on developing the range rather than the accuracy of their nuclear missiles, thus devaluing their offensive value.[23]This reinforces my deduction that the DPRK sees their nuclear arsenal playing a deterrent role rather than an offensive one.

Having ascertained that nuclear deterrence is prevalent on the Korean peninsula, the ODT predicts that war is unlikely to break out for three reasons. Firstly, the devastation that nuclear weapons can cause to states increases the cost of attacking indefinitely such that expansionist states are deterred from aggression. This is especially applicable to North Korea given its small territorial size[24] which will be devastated by a US nuclear strike. Secondly, the high costs also reduce the likelihood of preemptive strikes because the first-move dividend is small.[25] This prediction could explain then-US President Bill Clinton’s last minute decision not to exercise a military strike option to destroy the DPRK’s nuclear facilities.[26] Finally, arms race should not occur ’because the possession of an assured destruction capability’[27]will reduce the incentive to produce larger conventional forces while decreasing the likelihood of blunders that could trigger war. As such, the possession of nuclear weapons can be said to strengthen the defense, thus accounting for peace on the Korean peninsula.

Geography

The geography of the Korean peninsula has also contributed to the shift of the ODB towards the dominance of the defense. More specifically, the natural geography of the DMZ reduces the ease of conquest because of its harsh terrain conditions which inhibits offensive advancements while affording strong defensive positions to the defenders.[28] As the American geologist Cameron notes in his geological study of the eastern sector of the DMZ which forms the northern borders of the ROK,[29] the routes that connect North and South Korea are characterised by steep and broken terrains that are ‘segmented by long, narrow valleys.’[30] Consequently this results in ponderous travel by land; for example, heavy transports will require more than 90 minutes to traverse 20km of the aforementioned terrain. Thus, offensive movements are impeded, giving primacy to the defense. Conquest is also made harder by the presence of high ridgelines along the eastern DMZ which act as natural defensive positions from which invaders can be repelled.[31] Such a scenario was played out during the Korean War when ROK military commanders took up defensive artillery positions along the high ridgelines and managed to fend off North Korean military forces, inflicting upon them a 40% casualty rate in the process.[32] This reflects the advantage of the defense afforded by the natural terrain of the DMZ. Thus, conquest is hindered.

As a result of the geographical constraints posed by the DMZ, the ODT predicts that war is unlikely to occur on the Korean peninsula for two reasons. Firstly, the rewards for first move strikes are reduced. This is especially true in the Korean context because as a buffer zone that encompasses a vast geographical distance measuring 4-kilometer wide by 250-kilometer long,[33] the DMZ ensures that ‘little can be done with any material advantage gained by moving first.’[34] This is further compounded by the difficulty and time that aggressors will spend in navigating the aforementioned terrain, Secondly, the strategic positioning of the American troops noted in the earlier section and their function as a tripwire mean that the cost of attacking is increased, thus restricting the likelihood of war breaking out as a result of opportunistic expansion.

How the Offense-Defense Theory measures up against neoliberal institutionalism

Having examined how the ODT is capable of explaining the absence of a major war on the Korean peninsula, I turn to compare it with the theory of neoliberal institutionalism that also looks to account for peace so as to reinforce my argument for the validity of the ODT. Proponents of neoliberal institutionalism will look to explain the absence of war on the Korean peninsula by attributing this situation to the presence of international institutions that help mitigate the effects of anarchy and promote order.[35] According to Robert Keohane, international institutions ‘create the capability for states to cooperate in mutually beneficial ways by reducing the costs of making and enforcing agreements.’[36] This is done through negotiations which promote transparency, by implementing a system of rules and regulations in dealing with a specific issue thus creating a norm of path dependency that resolves issues in a peaceful manner and by ensuring the compliance of governments to their commitments undertaken during the negotiations. In the case of Korea, some of the institutions that have worked to promote peace on the peninsula include the Nuclear Non-Proliferation Treaty (NPT), the US-DPRK Agreed Framework and the Six-Party Talks. Consequently, a neoliberal will argue that peace ensues because these institutions have been capable of ‘reconciling conflicting interests’[37] without needing to resort to war.

However, drawing upon the issue of denuclearisation upon which most of the aforementioned institutions revolve, I argue that neoliberal institutionalism lacks the explanatory power that the ODT has in accounting for the absence of war on the Korean peninsula. This is because in light of the inconclusive Six-Party Talks since 2003 and in the face of North Korea’s withdrawal from the NPT in that same year[38], the effectiveness of institutional means to ameliorate nuclear tensions on the Korean peninsula can be called into question. Its ineffectiveness alludes to the weakness of the institutions under which circumstances the theory posits that there will be disorder with anarchy taking primacy in the international system, leading to an increased likelihood of war. The fact that this has not happened suggests that peace can be brought about by other means apart from international institutions. In this respect, the ODT and the predictions it generate because of the advantage the defense enjoys due to nuclear deterrence gains further credence.

Refinements to the ODT and further research

The case study of the prevalence of peace on the Korean Peninsula can serve as an instructive example towards refining the ODT. In the earlier sections, I have argued that the absence of a major war between North and South Korea can be attributed to the advantage the defense enjoys, which shifts the ODB towards the dominance of the defense. However, while this explains the opportunities for states to initiate wars, it does not account for the willingness of states to do so. This limitation is especially crucial with regards to North Korea where I have largely assumed that the decision to wage war is governed by a rationalist approach that will look to emphasize maximum utility. As such, North Korea should be deterred from attacking the South once it considers or perceives the overwhelming defensive advantage the South enjoys as a result of the US-ROK security treaty. However as Robert Gallucci argues, there is a chance that the North may attempt to wage war regardless of the high cost that they will incur if it appears that their regime is on the verge of economic and/or political collapse.[39] Further research might thus be undertaken with a view towards reconciling motives to wage war-which might be found at the societal level of analysis- with the opportunities to wage war that the ODT predicts.

Conclusion

In conclusion, I argue that the ODT is relevant for explaining the absence of war on the Korean Peninsula. Apart from examining the three indicators that point to the dominance of the defense, I have also elaborated upon some of the predictions of the ODT that accounts for peace when the defense enjoys the advantage. I have also compared the explanation that neoliberal institutionalism offers for the presence of peace and found those generated by the ODT to be more credible. All in all, it is apparent that the ODT is not invalidated by the absence of war between North and South Korea.

Bibliography

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Van Evera, Stephen. “Offense, Defense, and the Causes of War,” International Security, 22 (Spring, 1998): 5-43.

Waltz, Kenneth N. “The Spread of Nuclear Weapons: More May Be Better.” In Conflict After the Cold War: Arguments on Causes of War and Peace, edited by Richard K. Betts, 371-382. New York: Pearson/Longman, 2005.

[2] Stephen van Evera, “Offense, Defense and the Causes of War,” International Security, 22, 4 (Spring, 1998), 6.

[3] Yoav Gortzak, and Yoram Z. Haftel, and Kevin Sweeney, “Offense-Defense Theory: An Empirical Assessment,” The Journal of Conflict Resolution, 49, 1 (February, 2005), 68.

[4] The Avalon Project, Mutual Defense Treaty Between the United States and the Republic of Korea: October 1, 1953, http://avalon.law.yale.edu/20th_century/kor001.asp (accessed 22nd October 2010).

[5] Emerson M.S. Niou, “U.S. Security Commitments to South Korea and Taiwan: Extended Deterrence versus Dual Deterrence,” in A Changing Korea in regional and global context, eds. Lee-Jay Cho, Chung-Si Ahn and Choong Nam Kim (Seoul, Korea: Seoul University Press, 2004), 254.

[6] Terence Roehrig, From deterrence to engagement: the U.S. defense commitment to South Korea (Lanham, MD: Lexington Books, 2007), 181.

[7] Uk Heo and Terence Roehrig, South Korea since 1980 (New York: Cambridge University Press, 2010), 163.

[8] Associated Press, U.S. backs South Korea in punishing North, http://www.msnbc.msn.com/id/37309788/ns/world_news-asiapacific/ (accessed 23^rd October 2010).

[9] U.S. Department of State, Background notes: South Korea, http://www.state.gov/r/pa/ei/bgn/2800.htm (accessed 22nd October 2010).

[10]Associated Press, U.S. backs South Korea in punishing North, http://www.msnbc.msn.com/id/37309788/ns/world_news-asiapacific/ (accessed 23^rd October 2010).

[11] Terence Roehrig, From deterrence to engagement: the U.S. defense commitment to South Korea (Lanham, MD: Lexington Books, 2007), 181.

[12] BBC, President Barack Obama berates North Korea over Cheonan, 26^th June 2010, http://www.bbc.co.uk/news/10426209 (accessed 22nd October 2010).

[13] CNN, U.S., South Korea begin military exercises, 25^th July 2010, http://edition.cnn.com/2010/WORLD/asiapcf/07/24/south.korea.drills/index.html?iref=allsearch (accessed 22^nd October 2010).

[14] Stephen van Evera, Causes of War: structures of power and the roots of international conflict (Ithaca, New York: Cornell University Press, 1999), 123

[15] Keir A. Lieber, “Grasping the Technological Peace: The Offense-Defense Balance and International Security,” International Security, 25, 1(Summer, 2000), 97.

[16] Ibid.

[17] Kenneth N.Waltz, “The Spread of Nuclear Weapons: More May Be Better,” in Conflict After the Cold War: Arguments on Causes of War and Peace, ed. Richard K. Bett (New York: Pearson/Longman),372.

[18] Lars Assmann, Theater missile defense(TMD) in East Asia: implications for Beijing and Tokyo (New Brunswick, USA: Transaction Publishers, 2007), 325.

[19] Terence Roehrig, From deterrence to engagement: the U.S. defense commitment to South Korea (Lanham, MD: Lexington Books, 2007), 192

[20] Uk Heo and Terence Roehrig, South Korea since 1980 (New York: Cambridge University Press, 2010), 164.

[21] Terence Roehrig, From deterrence to engagement: the U.S. defense commitment to South Korea (Lanham, MD: Lexington Books, 2007), 192

[22] Ibid.

[23]Jae-Jung Suh, “The imbalance of power, the balance of asymmetric terror: mutual assured destruction (MAD) in Korea,” in The Future of US-Korean Relations: The imbalance of power, ed. John Feffer (London: Routledge, 2006),70.

[24] Edward A. Olsen, Korea, the divided nation (Westport, Connecticut: Praeger Security international, 2006),125.

[25] Stephen van Evera, “Offense, Defense and the Causes of War,” International Security, 22, 4 (Spring, 1998), 9.

[26] Jae-Jung Suh, “The imbalance of power, the balance of asymmetric terror: mutual assured destruction (MAD) in Korea,” in The Future of US-Korean Relations: The imbalance of power, ed. John Feffer (London: Routledge, 2006),68.

[27] Keir A. Lieber, “Grasping the Technological Peace: The Offense-Defense Balance and International Security,” International Security, 25, 1(Summer, 2000), 98.

[28] Stephen van Evera, “Offense, Defense and the Causes of War,” International Security, 22, 4 (Spring, 1998), 19.

[29]C.P. Cameron, “Dearly bought rides, steep access valleys, and staging grounds: The military geology of the eastern DMZ, central Korean Peninsula,” in Military geology in war and peace, eds. James R. Underwood and Peter L. Guth (Boulder, Colorado: The Geological Society of America, 1997), 85.

[30] Ibid., 87.

[31] Ibid., 93.

[32] Ibid., 90.

[33] CNN, Korea’s DMZ: The thin green line, 25^th August 2003, http://edition.cnn.com/2003/WORLD/asiapcf/east/08/22/korea.bio.dmz/(accessed 22^nd October 2010).

[34] Stephen van Evera, “Offense, Defense and the Causes of War,” International Security, 22, 4 (Spring, 1998), 9.

[35] Jack L. Snyder, “Averting Anarchy in the New Europe,” in Conflict After the Cold War: Arguments on Causes of War and Peace, ed. Richard K. Bett (New York: Pearson/Longman), 479.

[36] Robert O. Keohane, “International Institutions: Can Interdependence Work?” Foreign Policy, 110, Special Edition (Spring, 1998), 86.

[37] Jack L. Snyder, “Averting Anarchy in the New Europe,” in Conflict After the Cold War: Arguments on Causes of War and Peace, ed. Richard K. Bett (New York: Pearson/Longman), 479.

[38] Victor D. Cha and David C. Kang, “The Debate over North Korea,” Political Science Quarterly, 119, 2 (Summer, 2004), 230.

[39] Robert L. Gallucci, “America Deals with North Korea: A Realist’s Approach,” in Perspectives on structural realism, ed. Andrew K. Hanami (New York: Palgrave Macmillan), 157.

—

Written by:  Alvyn Ng
Written at: National University of Singapore
Written for: Dr. Terence Lee/ Maria Waqar
Date : October 2010

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