The Republic of Korea Armed Forces (), also known as the ROK Armed Forces, are the armed forces of South Korea. The ROK Armed Forces is one of the largest and most powerful standing armed forces in the world with a reported personnel strength of 3,600,000 in 2022 (450,000 active and 3,100,000 reserve).

The Republic of Korea Armed Forces traces its roots back to the establishment of the Korean Republic in 1919 as the armed wing of the Korean government-in-exile and was called the Korean Liberation Army wherein it conducted warfare against the Japanese occupation by conducting large-scale offensives, assassinations, bombings, sabotage, and search and rescue missions. Formally founded in 1948, following the establishment of the South Korean government after the liberation of Korea in 1945, South Korea's military forces are responsible for maintaining the sovereignty and territorial integrity of the state and also engage in peacekeeping operations, humanitarian and disaster relief efforts worldwide.

Although under South Korean control during peacetime, in wartime they are placed under the command of the United States through the CFC.

History

The origin of the Republic of Korea Armed Forces can be traced back to the Korean Independence Army, which was established by the Provisional Government of Korea in exile in Chongking, Republic of China in 1940 during the Japanese occupation of Korea. Many of its members became part of the South Korean armed forces later. In addition, some ethnic Korean Kuomintang and Manchukuo soldiers also contributed to the forces.

After Korea was liberated from the Empire of Japan on August 15, 1945, the Korean Constabulary () and the Korean Coast Guard (조선해안경비대, organized by Sohn Won-yil and others) were established through the United States Army Military Government in Korea. The Korean Constabulary and the Korean Coast Guard became the Republic of Korea Army and Republic of Korea Navy respectively, and formed the Republic of Korea Armed Forces after the South Korean government was established on August 15, 1948. The Republic of Korea Air Force was founded in October 1949.

The South Korean armed forces remained largely constabulary forces until the outbreak of the Korean War on June 25, 1950, requiring the United Nations to intervene with United States-led forces. The South Korean military rapidly developed during the Korean War, despite suffering enormous casualties. As the Soviets had armed North Korea, the U.S. armed and trained the South Korean military throughout the Korean War. After the Korean War, South Korea established a joint military partnership with the United States, termed the ROK-U.S. Alliance, as outlined by the Mutual Defense Treaty. During the Vietnam War, the ROK Army and ROK Marines were among those fighting alongside South Vietnam and the United States.

In the 1970s, through the Park Chung Hee Administration's "Yulgok Plan" (), South Korea began to build up self-reliant, national defense capability. The name derived from a scholar and an advisor to the king during the Joseon Dynasty. He had called out for an army of 10,000 men to keep the nation safe from any attacks. During South Korea's period of rapid growth in the 1980s, the military modernized, benefiting from several government-sponsored technology transfer projects and indigenous defense capability initiatives. In the 1990s, South Korean industries provided about 70 percent of the weapons, ammunition, communications and other types of equipment, vehicles, clothing, and other supplies needed by the military, and as of 2022, there are currently a total of 85 defense contractors in South Korea.

Today, the South Korean armed forces enjoy a mix of avant-garde as well as older conventional weapons. Its capabilities include many western weapon systems, complemented by a growing and increasingly more advanced indigenous defense manufacturing sector. For example, by taking advantage of the strong local shipbuilding industry, the ROK Navy has embarked on a rigorous modernization plan with ambitions to become a blue-water navy in the 2020s."North vs. South Korea: A Military Comparison." Global Bearings, 7 November 2011.

Future The ROK military forces are undergoing some preparation for assuming wartime operational control of the ROK's defenses. Several cutting-edge military systems are currently being inducted.

Based on the Moon Jae-in Administration's 'Defense Reform 2.0' (국방개혁 2.0) and in line with the overall troop drawdown scheme, the number of generals and admirals will be reduced by 17 percent from the current 436 to 360 by 2022 to reduce the bloated top command apparatus. This means the removal of 66 general-level positions for the Army and five each for the Navy and Air Force. At the same time, the ROK Armed Forces will see a reduction in active duty personnel from 640,000 to 517,000, and the length of compulsory military service will also be reduced to 18 – 22 months by 2022.

'Defense Reform 2.0' is also intended to make the ROK military more independent to prepare for the ROK military retaining operational control authority in wartime (OPCON transfer), rather than American general taking command. Initial operational control capability was verified in 2019, with full operational capability planned for 2021, and full mission capability planned for 2022.

Defense strategy

The signing of the Korean Armistice Agreement in 1953 by the Republic of Korea (South Korea) and the Democratic People's Republic of Korea (North Korea), ended the active hostilities of the Korean War. Since an official peace treaty has not been signed by North and South Korea, defensive actions needed to be implemented by the Republic of Korea Army in case of another North Korean attack.

During the Cold War era, a variety of anti-tank barricades were constructed over roads and railroad tracks leading in and out of Seoul, as well as within the Gyeonggi Province. The anti-tank barricades or "rock drops" are made up of giant concrete blocks mounted on thin walls, made to look like fake bridges and overpasses, that lead to nowhere but house hundreds of tons of rubble. These structures are rigged with explosives and are designed to be blown up by the South Korean Army which would drop the rubble blocking roads and railways. Along with the anti-tank barricades, the South Korean Army placed barbed-wire fences along the Han River and hundreds of 3-foot tall concrete pillars arranged in rows, known as "dragon teeth", across open fields. During the 1970s and 1980s when most of these structures were built, the goal was to slow down enemy tanks, troops, and other vehicles and to buy time for South Korean civilians to flee from the invading North Korean forces, as well as to allow for the Republic of Korea and the United States Army to employ troops to defensive positions. The South Korean Ministry of National Defense claims that the anti-tank barricades are inspected regularly for safety concerns, but the barricades show cracks and signs of erosion.

Local governments and civilians are now demanding that the anti-tank barricades be removed as they pose a great safety risk, obstruct new development, and many people believe have outlived their purpose. There are about 250,000 vehicles a day that pass by the barricades and their vibrations contribute to weakening the structures. Despite safety concerns, tearing down barricades is a complicated matter.

Since North Korea lost security and economic support from Russia in 1990 and China in 1992, a full-ground force assault on South Korea is unlikely according to military analysts. North Korea has changed its military tactics and now focuses on long-range and covert strikes. Through long-range artillery barrages, missile strikes, or chemical weapons that are used to deliberately attack non-American targets and short of all-out war, the North could seek to hold Seoul hostage with the hope of renegotiating a new status quo. Special warfare units are expected to use wartime tunnels or various infiltration means such as submarines, air-cushion vehicles (ACVs), AN-2 aircraft, and helicopters to infiltrate the forward and rear areas and conduct hybrid operations in the form of striking major units and facilities, assassinating key figures, and disturbing the rear area. The Defense Reform Base Plan was originally presented by President Roh Moo-hyun in December 2006, but after years of evolution, and political and military pushback the reform was launched by President Moon Jae-in's administration. The ROK Armed Forces will firmly implement Defense Reform 2.0 to proactively respond to changes in the security environment and omnidirectional security threats, as well as support peace and prosperity on the Korean Peninsula based on strength. To this end, the ROK Armed Forces will work toward "steadfast national defense.

On 27 December 2022 North Korea sent five drones over the border, one reaching Seoul. All five returned to the North, despite a five hour chase involving fighter jets and attack helicopters, with some 100 rounds being fired. A KAI KT-1 Woongbi crashed although both crew survived. The Joint Chiefs of Staff released a statement in which it acknowledges it can stop attack drones. However, its ability to stop smaller spy drones is "limited". A senior official, Kang Shin-chul, said: "Our military's lack of preparedness has caused a lot of concern to the people...actively employ detection devices to spot the enemy's drone from an early stage and aggressively deploy strike assets". The South Korean President Yoon Suk-yeol has indicated that South Korea will invest in stealthy drones that could penetrate North Korea with the creation of a new military unit.

The South Korean Defence Ministry announced a new series of anti-drone measures, spending some 560 billion won over the next five years. The money will go towards four new initiatives. One is an airborne laser that will be used to destroy larger drones whilst a jammer would be used on smaller drones. A new counter drone unit, made up of two squadrons, would also be created. The laser is already in the test process and is expected to become operational in 2027. The jamming system has been described as "soft kill". Further work will be done on stealth jets and anti-rocket artillery systems. The total amount of the spending over the next five years is 331.4 trillion. The previous Defence budget for the last financial year was just 54.6 trillion won as a comparison.

Command structure

Command over the ROK Armed Forces is established in the Constitution. The President is the Commander-in-Chief Forces ex officio. The military authority runs from the President to the Minister of National Defense, who is often to be (but not legally bound to be) a retired four-star general. The President and Minister of National Defense are in charge of the entire military establishment, maintaining civilian control of the military. The Minister of National Defense, by order of the President, takes charge of military affairs, and supervises the Chairman of the Joint Chiefs of Staff and the chief of staff of each service of the Armed Forces.

To coordinate military strategy with political affairs, the President has a National Security Council headed by the National Security Advisor.

Joint Chiefs of Staff

The Joint Chiefs of Staff consists of the Chairman of the Joint Chiefs of Staff, and the military service chiefs from the Army, Navy, and Air Force. Unlike the U.S. counterpart, operational command of combat units falls within the purview of the Chairman of the Joint Chiefs of Staff who reports to the Minister of National Defense.