A Unified Korea: Good for All (Except Japan)

Korea has a strong and unique history as it is ‘arguably the most ethnically homogenous country in the world with thirteen centuries of political unity and national and provincial boundaries older than almost any other state.’[1] Unification of the country had been in place since 668 (Common Era) during the Three Kingdoms Era—Silla, Goguryeo and Baekje (57 BCE–668 CE).[2]  The Gorguryeo Period rule was not able to withstand a growing power and preponderance of Japan.  The eventual outcome of this state-of-affairs would result in the annexation of Korea by Japan which effectively, shattered centuries of Korea’s domestic rule.  This problems for Korea would be compounded by World War Two (WWII) and the Korean War—both would add to the decline of a once great nation. Notwithstanding these two recent major happenings the desire on the part of the Korean peoples to have some semblance of unification has been growing; and there appears to be a slow but sure change for the better. Should it continue, there will be for all intent and purpose, a major change in the Asia-Pacific (A-P).

The core of the problem within the A-P is the non-resolution of the Korean War (1950–1953),[3] in which South Korean, United States of America (US) and United Nations’ (UN) forces fought the (North) Korean People’s Army and the Chinese People’s Volunteers Forces. Whilst North Korea’s intent (with the help of China and the Soviet Union) never came to be realised, the war also never officially ended.  With the recent political exchange and progress between the US, China, the Democratic People’s Republic of Korea (North Korea), and the Republic of Korea (South Korea) there is an attempt to bring about a final end to the war. The task-at-hand brings to the fore the possibility of a unification-of-sorts through the ending of the war. The unification process which was essentially, initiated by the Trump administration and notwithstanding the difficulties, if successful will throw up newfound issues in the region. Japan will unfortunately, will not be a beneficiary of the new political tide. A unified Korea will change the already complex geo-strategic balance in the region and simultaneously, produce a major new and powerful actor—a unified Korea. The possibility of Koreas being ‘one country’ and the ‘knock-on’ effect this will have on the A-P region cannot be assessed until the role Japan has had on the region, and in particular its relationship with the Koreas, being addressed.

Japan as an Asia-Pacific power

To be sure, it was the US that forced Japan out of its self-imposed isolationism during the mid-nineteenth century. Commodore Perry and his ‘black ships’ threatened to fire upon the port city of Edo (now Tokyo), if the Japanese government did not open up to trade with the West [4] (1853–1854). Whilst it was the American commander that demanded the opening the action was supported by European powers—in particular Britain, France and the Netherlands. The subsequent unification of Japan under the guidance of the Meiji Restoration (1895) and its subsequent mercantile efficiencies would allow Japan to prosper and this would be the beginning of Japan’s rise in the A-P.  Japan’s preponderance would grow through winning a war with China, in which Taiwan would be ceded (1894–1895), it would also go to war with Russia—the Japan-Russo War (1904–1905).Upon winning this war Japan would become further emboldened. As part of its regional ‘imperialism’[5] Japan would annexe the Korean Peninsula Korea (1910).  For Japan this was a strategic ‘necessity’ in order to circumvent Tsarist Russia’s regional expansionist tendencies and its subsequent ‘designs on Korea,‘[6], invade Manchuria (1931 and 1937[7]), and occupy Indochina (1939[8]). For all intents and purposes, Japan by the end of the 1930s had become a regional superpower.

With regard to Japan’s occupation of Korea, it would be enacted through the prism of the Japan–Korea Protectorate Treaty of 1905 (Ūlsa Treaty[9]), which was signed by King Kojong (Yi H’ui) the ruler of Korea (1897–1919) and allowed the Japanese to use the country as a military base; and place advisers in the government.[10] It should be noted that Kojong did not believe the annexation of Korea to be valid, and expressed this through sending letters to numerous newspapers (bearing his Royal seal) around the world.[11] As Japanese pressure mounted Kojong was forced into abdicating in 1907[12] and thus, the full extent of the Japanese annexation of Korea included the signed (albeit unwillingly) document that Korea ‘agreed to be guided by Japan,’[13] which was essentially, an affectation for subjugation. The suppression of Korea by Japan and its concomitant cruelties of colonial rule—which it must be stated was largely supported by the West[14]—consisted of

[T]op-down, centralized, direct and intensive powers … Commanding the military forces in the Peninsula, controlling a highly centralized police system, appointing all important local officials, and possessing broad legislative power as well as executive power, and [the Japanese] governor-general was a new authoritarian power in Korean political history.[15]

The opposing argument by Japan is that its tenure of rule had positive outcomes, as it ‘offered’ ‘Koreans reliable courts, a just financial system and honest weights and measures’ …  [nevertheless]  the Koreans were not satisfied with Japanese rule and rebelled in 1919, declaring themselves independent.’[16]  Japan’s interventions in Korea and the subsequent treatment of Koreans, and in particular the bitter war the Japanese waged against the Korean people in the sixteenth century,[17] has resulted in Japan being labelled by Koreans as an ‘accursed nation.’[18]

The taking of Korea would be a part of the power-based ambitions of Japan and reinforce the notion that to be a modern power was to be a colonising power.[19]  Within its sphere of domestic irredentism and extramural ventures, Japan’s A-P successes would include control of Taiwan; the annexing of Manchuria (1931); invading Nanjing (1937); and entering a tripartite pact with Germany and Italy (1941).  The ambitions would eventuate in the Pacific phase of WWII being initiated through its ‘surprise attack’ on Pearl Harbor, which would lead to subjugating Malaya and controlling the archipelagos of the Philippines and Indonesia (1942),[20] and extending its stretch into Oceania.  The ‘empire overstretch’ would be so great however, it would retard Japan’s protection of its homeland and bring about total surrender. To wit,

Japan’s air force—not only its aircraft but its skilled pilots as well—had virtually ceased to exist. Its merchant marine lay at the bottom of the ocean. Almost all of the country’s major cities had been fire-bombed, and millions of the emperor’s loyal subjects were homeless. The defeated imperial army was scattered throughout Asia and the islands of the Pacific Ocean, its millions of surviving soldiers starving, wounded, sick and demoralised.[21]

Japan was subsequently and progressively relieved of its colonies after its unconditional surrender to the US in 1945. Korea would return to a UN authorised independence in 1948.  Frictions between the two Koreas however, remain to this day as well as and due to the past between the Koreas and Japan. The dynamics of the region will change if an irenic agreement comes to pass and what the unification will comprise can now be addressed.

The reality of Korean ‘unity’

Based on the history of the two Koreas it should be noted that it is politically impossible to achieve an absolute reunification unless a forced alignment was to occur.   The way in which absolute reunification occurs is often through a victory via a war and a recent example of this is writ large in the  total victory of North Vietnamese forces at the end of the Vietnam War (1963–1975).[22] Using the Vietnam War as an example is pertinent in order to show that unification through limited war is definitive in its outcome, as it provides an unambiguous power-base to the winner. Hence, it would take a restart of the Korean War to gain the same ‘type’ of unification of the Koreas as Vietnam.  Notwithstanding this, there is no ‘political appetite’ for this to happen as the dangers of the Koreas undertaking such a pathway would pose enormous problems for them and the region.  The overriding problem would be it would have the potential to draw in other actors and could thereby, escalate into a total war.  This would be due to the most powerful A-P actors—China, the US, and possibly Russia—becoming involved. Notwithstanding the aforementioned, it would require an inordinate leap of faith on the part of both North and South Korea to achieve total unification and as such this will not take place. There is however a considerable possibility that a form of ‘bilateral reconciliation’[23] will come to pass, although the reason the two countries cannot and will not seamlessly merge into one, is in the current political climate and due to the historic power-stakes a requirement of the ceding of power by one actor to the other would need to take place. This too, cannot and will not take place. Both Koreas would not be willing to cede their politico-status and more importantly their military power as the repercussion would be an immediate ‘security dilemma’[24] being created for both actors; and moreover, it would also create cultural shame and a ‘loss-of-face’ predicament. This too, would not be acceptable to either actor, or their respective populaces.  .

With the abovementioned factors in mind, there is under both Korean administrations—including their major allies, China for North Korea, the US, Australia and Japan for South Korea—at least a desire to elicit an irenic outcome and finally bring about an end to the Korean War.  Such a happening will not only present a greater degree of stability in the region as a result of the lessening of decades-long tensions it will also assist in returning Korea to the profoundly politically-mature nation it once was.  This is where the problems for Japan will begin in earnest, however and in order to understand the situation a brief, analysis of what is currently and actually happening is required.

North Korea’s Supreme Leader Kim Jong-un has moved beyond the isolationism of previous decades, with perhaps the most important visits being China, South Korea and more recently Singapore at the behest of US President Trump, in March, April and June 2018 respectively.[25] Whilst it is impossible to predict the continuation of the current diplomacy and its impacts, what has become clear is a triad: there has been a significant shift in bilateral relations between the two Koreas; China remains the linchpin of North Korea’s survival; and the current Trump administration is noticeably enthusiastic to lessen the threat of another war on the Korean peninsula becoming a reality—if only due to American forces being drawn into yet another, interminable war. To be sure, an irenic agreement also offers a chance for North Korea, and thereby Kim Jong-un to become a more cosmopolitan regional and international actor;  offers greater economic prosperity to his people; and significantly reduces the use of brinkmanship—in this case the threat of missile strikes—as a mechanism to gain greater regional status. The upshot of all the aforementioned for Japan is that it will face a will be vastly different neighbour, than it has been. This factor can now be examined.

Japan’s coming predicament: facing three united countries

Japan has been a significant A-P post-WWII regional power. This is due to its military status per se and its, post-WWII links to US forces—especially with the ongoing presence of a large US military contingent on Okinawa. Additional to this, Japan has had a successful industrial revolution in the 1970s which allowed it to become an ongoing international economic power which also remains the case in contemporary times. From a political perspective Japan has also been able to positively exploit its mutually-allied US–South Korea partnership due to North Korea remaining consistently belligerent. The issue for Japan is a change in the level of co-operation between the Koreas would cause a re-alignment of allegiances and this would place significant pressures on Japan, as the deep-seated animosities that linger between South Korea and Japan are veiled, and the allegiance of South Korea and Japan is largely due to North Korea’s continuing recalcitrance. This will change upon any decrease in the current frictions between the Koreas, and Japan will be forced to deal with a two reinvigorated countries with a barely-concealed hostility. This is writ large in the current currently  Japan -South Korea relationship in that even though they both share similar political and societal developments in the sense they are liberal-democracies, highly-developed and industrialised countries and have had significant security issues with North Korea it does not diminish the fact that the relationship between the two remains fraught with historical tensions.[26]

Three which it can be argued, that affect the relations are the general post-WWII ill-treatment of Koreans that reside in Japan (which has been criticised by the UN); the signing of the 1965, Treaty on Basic Relations[27] in which the South Korean government cannot claim war reparations from Japan; and the sexual slavery of Korean women—euphemistically referred to as ‘comfort women’—by the Japanese military forces in WWII.[28] These issues will immediately return to the fore and have an enormous impact on Japan should the Korean Peninsula become less fractious. Whilst the aforementioned issues will be problematic for Japan the problem that will eclipse the Koreas uniting will consist of a knock-on effect: a greater alignment with China will take place. This will be due to China positively and opportunistically exploiting the unification of the Koreas as a chance to improve its preponderance in the region and elsewhere. China too has long-term animosity toward Japan and it will use the unity for its own politico- and military-leverage and the offshoots will consist of, but not be limited to China being more aggressive in its Arunachal Pradesh border dispute with India; enable the retrocession of Taiwan to be more forthrightly pursued; and the ‘Belt and Road’ and South China Sea initiatives will be able to progress more efficiently. The de-escalation of problems within the Koreas will allow China to place more effort on the regional components mentioned and whether China is successful in its claims is moot and need not be discussed further here. What is of interest here is the way in which the catharsis of a new set of China – Japan relations will further pan out, as the already corrosive relations become more prominent. The single issue which will gain more credence—as it will have the direct support of the two Koreas—is directly supplanted in the two invasions of China by Japanese forces in the early twentieth century—especially the 1937–1938 Nanking massacre;[29]—and are directly reflected in ‘China’s relations with Japan have long been poisoned by what Beijing sees as Tokyo’s failure to atone for its occupation of China before and during World War Two.’[30] This factor, it can be argued, has had more relevance in regional machinations due to Germany having apologised for its part in WWII, and moreover it is without doubt that such an undertaking does offer a significant contribution to irenic relations between nation-states.[31] Certainly, a more direct and forthright united front that Japan will face from its neighbours will impact heavily upon its place in the region.


There is ample historical evidence that when a country has domestic stability, reliable allies and a powerful military that allows irredentism and expansionism to flourish. Throughout history America, China, England, France, Iraq, Israel, Spain and many other nation-states are testament to this taking place. Others however, are often directly impacted upon and this is true of Hawaii being usurped by America; China and its taking of Tibet; France in its invasion of Russia; England and the seizing of India; Iraq and its invasion of Kuwait; Israel and the taking of East Jerusalem/West Bank; and Spain undertaking the conquest of the South Americas. As stipulated Japan and its irredentist policies within the region have created tensions means that as the Koreas gain greater harmony they will assert a more co-ordinated approach toward Japan’s past deeds and its present ambitions. This, combined with China’s preponderance will heavily, and negatively, impact on Japan. The way in which Japan will respond to these pressures remains to be seen, however any China-North Korea-South Korea quasi-tripartite or direct agreement would see a coalescing of historical animosities which must place strategic pressures on Japan. For instance, a unified Korea, regardless of not being a single sovereign nation-state and albeit, with two distinctive regions will nonetheless, identify more strongly as ‘one people with a shared history’ and set about diminishing Japanese politico- and military-influence An immediate outcome it can be safely argued, would be the two Koreas being less inclined to directly criticize China’s overt military role in the South China Sea per se; would explicitly favour China’s claims on the Senkaku Islands/Diaoyu Islands in the East China Sea; and would side with China in rejecting Japan’s attempt to become part of the UN Security Council’s permanent members. All would directly impact upon Japan’s ‘middle power‘ status. The regeneration of what would constitute a new Korea would be to elevate the difficulties for Japan and if this were to be in parallel with the US remaining on its current pathway of further developing quasi-isolationist tendencies and remained true to its mantra of wanting its allies to ‘do more’ in building their own defence capabilities will also add to Japan’s woes.

The outcome of a unified two Koreas living in (relative) harmony with each other would place Japan in a newfound politico- and regional-strategic situation in which it would have to come to terms when facing two semi-united countries; and a unified country. Simply put, all three countries have long-term deep-seated animosity toward Japan and a unification-of-sorts would offer the opportunity for retaliation, or a quasi-revenge to take place. Going to war against Japan however, is highly-unlikely as it would draw in other powerful actors—this is not what either country wants. Notwithstanding this, China, North Korea and South Korea will do all they can to constrain Japan. Any decrease in tensions on the Korean Peninsula would be good for the world from the perspective of a ‘kinetic exchange’ or a ‘shooting war’ not breaking out. Paradoxically however, the peace will introduce a completely new set of enormous politico- and military-challenges for Japan, as it is forced to endure the repressed rage of its closest neighbours finally coming to the political surface.


[1] Michael Seth.  A History of Korea.  From Antiquity to the Present.  Lanham: Rowman and Littlefield Publishers   Inc, 2011, 2.

[2] See: ‘Three Kingdoms Period in Korea Timeline.’  Ancient History Encyclopedia https://www.ancient.eu/timeline/Three_Kingdoms_Period_in_Korea/

[3] See: ‘Korean War.’ History.com  https://www.history.com/topics/korea/korean-war

[4] Kim Ji-hyung.  ‘The Japanese Annexation of Korea as Viewed from the American and British Press: focus on The Times and The New York Times.’  International Journal     https://ijkh.khistory.org/upload/pdf/03._IJKH_16-2_Kim_JI-hyung.pdf

[5] Imperialism’ consists of ‘the projection of political power across large spaces to include other states.’  See: Robin Butlin.  Geographies of Empire.  European empires and colonies, 1880 – 1960.  Cambridge: Cambridge University Press, 2009, 6.

[6] Japan and Korea since 1910,’ 52.

[7] David Day.  Conquest.  A New History of the Modern World.  Sydney: HarperCollins Publishers, 2005, 196-197.

[8] For a full account of Japan’s military expansionism see: ‘Japan profile – Timeline.’  BBC News.  20Feb, 2018. https://www.bbc.com/news/world-asia-pacific-15219730

[9] A History of Korea.  From Antiquity to the Present, 265 – 266. 

[10] ‘Kojong.  Korean Ruler.’ Encyclopædia Britannica.   The Editors of Encylopædia Britannica. https://www.britannica.com/biography/Kojong

[11] See:  The Japanese Annexation of Korea as Viewed from the American and British Press: focus on The Times and The New York Times, 88.

[12] ‘Kojong.  Korean Ruler.’ Encyclopædia Britannica.

[13]  Japan and Korea since 1910,’ 49 – 50.

[14] The Japanese Annexation of Korea as Viewed from the American and British Press: focus on The Times and The New York Times, 116.

[15] A History of Korea.  From Antiquity to the Present, 265 – 266. 

[16] Clarence Gilliland.  ‘Japan and Korea since 1910.’  JSTOR.  University of California: University of       California Press, 1920.  https://www.jstor.org/stable/pdf/41168782.pdf

[17] ‘Japan and Korea since 1910,’ 47.

[18] ‘Japan and Korea since 1910,’ 47.

[19] Tim Harper.  ‘Japan’s giant second world war gamble.’  The Guardian, 7 Sep, 2009. https://www.theguardian.com/world/2009/sep/07/japan-imperialism-militarism

[20] ‘Japan’s giant second world war gamble,’   The Guardian. 

[21] John Dower. Embracing Defeat.  Japan in the Wake of World War II. W W. Norton and Co: New York, 1999, 43.

[22] The Vietnam War is ‘known as the “American War” in Vietnam.’  See: British Broadcasting Corporation. Timeline: Vietnam.


[23] John Nillson-Wright.  ‘Koreas summit:  Will historic talks lead to a lasting peace?’ BBCNews. 28 Apr, 2018.  https://www.bbc.com/news/world-asia-43932032

[24] Security uncertainty exists in the international arena between nation-states according to Herz in the form of a ‘security dilemma.’ This is a process in which each constellation/group ‘must be, and usually are, concerned about their security from being attacked, subjected, dominated or annihilated by other groups and individuals.  Striving to attain security from such attack, they are driven to acquire more and more power in order to escape the impact of the power of others … ’ See: John Herz. “Idealist Internationalism and the Security Dilemma.’ World Politics, Vol. 2, Jan, 1950, 157.  http://www.jstor.org/view/00438871/di971097/97p0057z/0

[25] For a complete list of places visited by the North Korean Supreme Leader see:  ‘Kim Jong un Fast Facts.’ CNN.  https://edition.cnn.com/2012/12/26/world/asia/kim-jong-un—fast-facts/index.html

[26] Brad Glisserman.  ‘Japan-South Korea: So close, yet so far.’  The Diplomat. 28 Feb, 2018.  https://thediplomat.com/2018/02/japan-south-korea-so-close-yet-so-far/

[27] Wi Tack-whan and Chang Iou-chung ‘1965 Korea – Japan agreement should be re-estimated.’ Korea.net. 23 Mar, 2016.  http://www.korea.net/NewsFocus/History/view?articleId=134245

[28] Ruper Wingfield- Haynes.  ‘Japan revisionists deny WW2 sex slave atrocities.’  BBCNews  3 Aug, 2015               https://www.bbc.com/news/world-asia-33754932

[29] See: ‘The  Rape of Nanking.’ History.com. The Editors of History.com.


[30] Chehui Peh and Teppei Kasai. ‘Asian neighbours protest as Japan PM sends war offering to war dead shrine.’  Reuters.  15 Aug, 2017https://www.reuters.com/article/us-ww2-anniversary-japan-idUSKCN1AV009

[31] ‘Many praise Germany, scorn Japan 70 years after WWII.’ Japan Times. 13 Aug, 2015.  ttps://www.japantimes.co.jp/news/2015/08/13/national/history/70-years-wwii-neighbor-states-hold-germany-high-heap-scorn-axis-ally-japan/#.W7bldHszbIU

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