The organization of the modern South Korean, also known as the Republic of Korea (ROK), armed forces started at the end of War World II after the Japanese surrendered to Allied Forces and the Korean peninsula was divided at the 38th parallel, between American and Soviet occupations. The South Korean Constabulary, the forerunner to the ROK Army, was established under the United States Army Military Government in Korea (USAMGIK), the ruling body of the southern half of the Korean Peninsula from 1945 to 1948. The formation of the constabulary was tumultuous as USAMGIK leadership was deeply suspicious of Korean loyalties and the organization lacked knowledge of Korea’s political situation and language. Thus, the constabulary failed to attract many of the estimated 100,000 Koreans that fought with either the Chinese Nationalists or Communists against Japan, relied heavily on Korean officers trained and educated by the Japanese, and accepted communist-leaning recruits to depoliticalize the military. Moreover, to avoid provoking the North and stoking Southern military adventurism, the United States limited the resources provided to the South Korean military to infantry-type weapons and training. Subsequently, when the US withdrew all but a handful of its troops in August 1949 and the South Korean government was established, the newly formed Republic of Korea Army was factionalized, undertrained, and under-resourced. The ROK Army would not change significantly before North Korea invaded the South in June 1950.

After the Korean War every South Korean division had an American Colonel seated with the Korean division commander. The United States provided arms and other resources to the South Korean military. This lasted until the early 70s when Korean troops were sent to Vietnam. The Korean government took half the pay, and that money was invested in military infrastructure. Soldiers went to Vietnam with M1 rifles and Carbines and came back with M16s and M60 machine guns.

The gradual reduction of US forces, which started at the close of the Korean War in 1953, prompted the establishment of the ROKUS Combined Forces Command (ROKUS CFC) in 1978. The ROKUS CFC integrated the US and ROK (Republic of Korea) military at the theater level and were bound by four annual exercises that were ultimately consolidated into the Foal Eagle and Ulchi Freedom Guardian (UFG) exercises. The big brother-little brother relationship continued. It was a cordial relationship, but it left little room for Koreans to grow to be a professional army.

Although there was some resentment in the ROK military about being the little brother to their US counterpart, the majority of soldiers had the greatest respect for American military might and the values and humanity of the United States. As a result of this high regard, South Korean military elites sidestepped their job to focus on personal advancement. Most US commanders never saw the true nature of their Korean soldiers because they were reluctant to leave the base and hypnotized by the dog and pony show of the South Korean military. The short tours of most American soldiers and senior officers did not help. In 1994, the United States transferred Armistice operational control (OPCON) to the South Korean military. In other words, South Korea would control its troops during peacetime. However, a US commander would assume control of troops in the event of war with North Korea. The general mood between US and ROK leadership was dependent on the personal characters of the individuals involved. Some valued the alliance, some paid it lip service, and some plainly ignored it.

In 2002, a progressive government led by Korean president Roh Moo-hyun was elected. Roh was biased and misinformed about the ROKUS military relationship especially the command structure. Subsequently, the issue of transferring wartime OPCON to Korea dominated ROK-US affairs. The United States was preoccupied with wars in Afghanistan and Iraq and the Bush administration was obtuse about the implications of a fundamental change of the command structure. Both ROK and US military leaders strived to maintain the relationship. But senior military officials remember how close the Bush administration came to leaving Korea to its own devices.

During the following two conservative Korean administrations, the issue of OPCON did not receive the attention it deserved but was delayed with vague reasoning. With North Korean nuclear development becoming a visible reality, OPCON issues were not a priority. North Korean direct military actions, including the sinking of a South Korean frigate and the shelling of Yoen-Pyeong Island, contrasted the difference of priorities between Seoul and Washington. Seoul wanted retaliation and Washington wanted restraint. The difference in priorities caused inevitable friction at the military level. Still the relationship remained cordial and friendly.

The Moon Jae-In administration inherited Chinese pressures from the deployment of THAAD, an antimissile battery , and a nuclear armed North Korea. Additionally, as previous progressive administrations had cultivated higher expectations of leaders within Korean society, the electorate was more inclined to question executive policy. Moon tried to make peace with China and North Korea, an action that opened the flood gates for domestic criticism of the ROK military. Two phenomena arose from this torrent of criticism. Firstly, training drills at live fire ranges were halted in response to complaints from Koreans living close to these installations. Secondly, commanders, intimidated by a wave of internal accusations of hazing and poor living conditions within the military, became reluctant to conduct realistic training as it put their subordinates at greater risk for fatality or serious injury. The controversy surrounding training has had a deleterious effect on combat readiness. To this point, there are some tank units that have not fired at night for ten years.

Relations between US and ROK military leaders had never been as fractious as they were under the Moon administration. Frustrations arose from delays in providing a base to host the THAAD battery, opposition to live-fire training, and the implications of OPCON issues for the future of the United Nations Command (UNC), the UN body currently enforcing the Armistice Agreement on the Korean peninsula. However, little friction resulted from the Comprehensive Military Agreement and the cessation of combined exercises. Fortunately, the last days of Moon’s administration has been responsive to these issues and ROK military leaders have worked to address some of these situations.

South Korea’s newly elected president, Yoon Suk-yeol, took office in May. He inherits a hostile world that is polarized with China and the United States as adversaries. Korea needs to mend its relations with Japan, fully resolve military training issues, and develop a common vision for the UNC. As all these issues are being negotiated, the US and ROK militaries must actualize each other’s roles and understand the limitations constraining each organization. The two militaries must, above all, be ready to deter North Korean provocation and aggression. While the slogans “ Fight tonight ” and “ Let's go together ” are commonly used to encapsulate the US-ROK alliance, living up to these ideals for combat readiness and cooperation will require an unshakeable resolve that does not play to political whims.

In-Bum Chun, a retired lieutenant-general and former Commander of ROK Special Warfare Command, explains how the "South Korean Constabulary, the forerunner to the ROK [South Korean] Army, was established under the United States Army Military Government in Korea..." and how the ROK Army evolved to the present day in close cooperation with its US counterpart.

Additional titles in the Asia Pacific Bulletin series

The organization of the modern South Korean, also known as the Republic of Korea (ROK), armed forces started at the end of War World II after the Japanese surrendered to Allied Forces and the Korean peninsula was divided at the 38th parallel, between American and Soviet occupations. The South Korean Constabulary, the forerunner to the ROK Army, was established under the United States Army Military Government in Korea (USAMGIK), the ruling body of the southern half of the Korean Peninsula from 1945 to 1948. The formation of the constabulary was tumultuous as USAMGIK leadership was deeply suspicious of Korean loyalties and the organization lacked knowledge of Korea’s political situation and language. Thus, the constabulary failed to attract many of the estimated 100,000 Koreans that fought with either the Chinese Nationalists or Communists against Japan, relied heavily on Korean officers trained and educated by the Japanese, and accepted communist-leaning recruits to depoliticalize the military. Moreover, to avoid provoking the North and stoking Southern military adventurism, the United States limited the resources provided to the South Korean military to infantry-type weapons and training. Subsequently, when the US withdrew all but a handful of its troops in August 1949 and the South Korean government was established, the newly formed Republic of Korea Army was factionalized, undertrained, and under-resourced. The ROK Army would not change significantly before North Korea invaded the South in June 1950.

After the Korean War every South Korean division had an American Colonel seated with the Korean division commander. The United States provided arms and other resources to the South Korean military. This lasted until the early 70s when Korean troops were sent to Vietnam. The Korean government took half the pay, and that money was invested in military infrastructure. Soldiers went to Vietnam with M1 rifles and Carbines and came back with M16s and M60 machine guns.

The gradual reduction of US forces, which started at the close of the Korean War in 1953, prompted the establishment of the ROKUS Combined Forces Command (ROKUS CFC) in 1978. The ROKUS CFC integrated the US and ROK (Republic of Korea) military at the theater level and were bound by four annual exercises that were ultimately consolidated into the Foal Eagle and Ulchi Freedom Guardian (UFG) exercises. The big brother-little brother relationship continued. It was a cordial relationship, but it left little room for Koreans to grow to be a professional army.

Although there was some resentment in the ROK military about being the little brother to their US counterpart, the majority of soldiers had the greatest respect for American military might and the values and humanity of the United States. As a result of this high regard, South Korean military elites sidestepped their job to focus on personal advancement. Most US commanders never saw the true nature of their Korean soldiers because they were reluctant to leave the base and hypnotized by the dog and pony show of the South Korean military. The short tours of most American soldiers and senior officers did not help. In 1994, the United States transferred Armistice operational control (OPCON) to the South Korean military. In other words, South Korea would control its troops during peacetime. However, a US commander would assume control of troops in the event of war with North Korea. The general mood between US and ROK leadership was dependent on the personal characters of the individuals involved. Some valued the alliance, some paid it lip service, and some plainly ignored it.

In 2002, a progressive government led by Korean president Roh Moo-hyun was elected. Roh was biased and misinformed about the ROKUS military relationship especially the command structure. Subsequently, the issue of transferring wartime OPCON to Korea dominated ROK-US affairs. The United States was preoccupied with wars in Afghanistan and Iraq and the Bush administration was obtuse about the implications of a fundamental change of the command structure. Both ROK and US military leaders strived to maintain the relationship. But senior military officials remember how close the Bush administration came to leaving Korea to its own devices.

During the following two conservative Korean administrations, the issue of OPCON did not receive the attention it deserved but was delayed with vague reasoning. With North Korean nuclear development becoming a visible reality, OPCON issues were not a priority. North Korean direct military actions, including the sinking of a South Korean frigate and the shelling of Yoen-Pyeong Island, contrasted the difference of priorities between Seoul and Washington. Seoul wanted retaliation and Washington wanted restraint. The difference in priorities caused inevitable friction at the military level. Still the relationship remained cordial and friendly.

The Moon Jae-In administration inherited Chinese pressures from the deployment of THAAD, an antimissile battery , and a nuclear armed North Korea. Additionally, as previous progressive administrations had cultivated higher expectations of leaders within Korean society, the electorate was more inclined to question executive policy. Moon tried to make peace with China and North Korea, an action that opened the flood gates for domestic criticism of the ROK military. Two phenomena arose from this torrent of criticism. Firstly, training drills at live fire ranges were halted in response to complaints from Koreans living close to these installations. Secondly, commanders, intimidated by a wave of internal accusations of hazing and poor living conditions within the military, became reluctant to conduct realistic training as it put their subordinates at greater risk for fatality or serious injury. The controversy surrounding training has had a deleterious effect on combat readiness. To this point, there are some tank units that have not fired at night for ten years.

Relations between US and ROK military leaders had never been as fractious as they were under the Moon administration. Frustrations arose from delays in providing a base to host the THAAD battery, opposition to live-fire training, and the implications of OPCON issues for the future of the United Nations Command (UNC), the UN body currently enforcing the Armistice Agreement on the Korean peninsula. However, little friction resulted from the Comprehensive Military Agreement and the cessation of combined exercises. Fortunately, the last days of Moon’s administration has been responsive to these issues and ROK military leaders have worked to address some of these situations.

South Korea’s newly elected president, Yoon Suk-yeol, took office in May. He inherits a hostile world that is polarized with China and the United States as adversaries. Korea needs to mend its relations with Japan, fully resolve military training issues, and develop a common vision for the UNC. As all these issues are being negotiated, the US and ROK militaries must actualize each other’s roles and understand the limitations constraining each organization. The two militaries must, above all, be ready to deter North Korean provocation and aggression. While the slogans “ Fight tonight ” and “ Let's go together ” are commonly used to encapsulate the US-ROK alliance, living up to these ideals for combat readiness and cooperation will require an unshakeable resolve that does not play to political whims.