OPLAN 5027

Operations Plan 5027 (OPLAN 5027) are a series of military operations plans made by the United States and South Korea for the defense against a possible North Korean invasion.^[1]

History

Before 1973, OPLAN 5027 was primarily focused on defeating a North Korean invasion, with a 50-mile retreat from the penetrated Demilitarized Zone to positions south of the Han River (known as the Hollingsworth Line). Allied forces would then wait for American reinforcements before counterattacking.

With the withdrawal of the United States from Vietnam and concerns of North Korea doubting America's commitment to defend South Korea, Combined Forces Commander US General James F. Hollingsworth developed a forward-based offensive strategy known as OPLAN 5027-74. The new plans called for most artillery, tanks, and infantry to be moved toward the Military Control Zone five miles south of the Demilitarized Zone. Offensive strategies following the defeat of invasion forces included two brigades of the US 2nd Division to seize the nearby city of Kaesong, around-the-clock B-52 bomber raids, and a "violent, short war" to capture the capital city of Pyongyang. No mention was made of the use of tactical nuclear weapons in case of overwhelming North Korean forces, though the Congressional Budget Office predicted that without their use, the new strategy could result in the initial loss of Seoul.

1994 U.S, North Korea stand-off Part of the Korean Conflict Date May 1994 (Hypothetical) Location North Korea, South Korea Result Never took place Belligerents  South Korea  United States  North Korea Commanders and leaders Kim Young-sam Bill Clinton Kim Il-sung Casualties and losses South Korea: 490,000 killed and wounded[2] United States: 52,000 killed and wounded[3] Enormous civilian and military losses[4]

Korean War North Korean Offensive Pokpoong Chuncheon 1st Seoul Gorangpo Kaesong-Munsan Korea Strait Ongjin Uijeongbu Suwon Airfield Air Campaign Andong Chumonchin Chan Osan Pyongtaek Chonan Chochiwon Taejon Sangju Yongdong Hwanggan Hadong Notch Pusan Perimeter Masan P'ohang-Dong Taegu 1st Naktong Bulge Bowling Alley Battle Mountain Kyongju Haman Nam River Ka-San Tabu-Dong Yongsan 2nd Naktong Bulge UN Command Counteroffensive Haeju Inchon 2nd Seoul Hill 282 12 October 1950 Sariwon Pyongyang Yongju Kujin Chongju Chinese Intervention Onjong Unsan Pakchon Ch'ongch'on River Wawon Chosin Reservoir Task Force Faith 3rd Seoul Uijeongbu Chaegunghyon 1st and 2nd Wonju Thunderbolt Twin Tunnels Hoengsong Chipyong-Ni 3rd Wonju Chuam-Ni Wonsan Killer Ripper Maehwa-San Courageous Tomahawk Rugged Dauntless Spring Offensive Imjin River Yultong Kapyong Soyang River Stalemate Bloody Ridge Minden Punchbowl Heartbreak Ridge Han River Commando 1st Maryang San Haktang-ni Polecharge 2nd Maryang San Sunchon Hill Eerie Sui-Ho Dam Old Baldy Blaze White Horse Triangle Hill 1st Hook 2nd Hook Chatkol Outpost Vegas Pork Chop Hill 3rd Hook Outpost Harry Kumsong Samichon River Korean Armistice Agreement Air operations MiG Alley Sunchon Strangle Sui-ho Dam Post Armistice D.M.Z. Conflict Blue House Raid EC-121 Incident Axe murder incident Gangneung Border Incidents Yosu 1st Yeonpyeong 2nd Yeonpyeong Daecheong Cheonan sinking 3rd Yeonpyeong North Korea crisis , Division of Korea Post-armistice conflicts DMZ conflicts 1966–1969 conflict Blue House Raid Major Henderson incident Axe murder incident Terror attacks Rangoon bombing KAL Flight 858 NLL conflicts 1st Yeonpyeong 2nd Yeonpyeong Daecheong Cheonan incident 3rd Yeonpyeong Other maritime incidents Pueblo incident EC-121 shootdown Gangneung Yosu 2013 Korean crisis South Korea cyberattack Panama ship seizure Post-crisis threats

A variant of the operation plan, OPLAN 5027-94, was reportedly under consideration by CINCPAC in 1994 for a scenario where South Korean forces could halt a North Korean invasion and stabilize a defensive line at FEBA Bravo, twenty to thirty miles from the DMZ. With the arrival of American reinforcements, a major air campaign would be waged against North Korea before a land offensive by a US Marine Expeditionary Force (in division strength), the 82nd Airborne Division, and South Korean divisions towards Wonsan. A combined US-ROK force would also stage an amphibious landing near Wonsan, with the two forces joining together for an advance on Pyongyang. The scenario depended on South Korean forces holding out against a North Korean advance for an initial 5–15 days, as well as potentially another 15–20 days during preparations for the counteroffensive.

Following concerns over a North Korean nuclear program, OPLAN 5027 was completely overhauled with OPLAN 5027-96, which included a new agreement with the Japanese government for the use of Japanese bases in the event of a war. Further revisions and more detailed offensive strategies were incorporated in late 1998 into OPLAN 5027-98, with new focus on countering sudden chemical and biological attacks against Seoul. Reports claim that the operation would be divided into four phases: activities prior to a North Korean attack (preemptive attacks against military bases on strong intelligence of invasion preparations), halting an initial North Korean assault, regrouping for counterattacks, and a full-scale invasion of North Korea to seize Pyongyang (with a strategy of maneuver warfare north of the Demilitarized Zone with a goal of terminating the North Korean regime). When OPLAN 5027-98 was leaked to the press in November 1998, tensions escalated, with North Korea calling the plan a war scenario for invasion.

Details have emerged on subsequent revisions to the operation plan, including an increased Korean deployment of 690,000 troops in OPLAN 5027-00 in the event of the United States being involved in a two-front war, updates in OPLAN 5027-02 in light of the September 11th attacks and the Bush Doctrine of pre-emptive military action (even without consulting South Korea), larger substitution of air power (missiles and UAVs) for ground forces and artillery in OPLAN 5027-04 and OPLAN 5027-06, and a multi-year realignment of American forces in OPLAN 5027-08.

Scenarios

Most known versions of OPLAN 5027 assume a surprise attack by North Korea, with the initial intent of destroying allied defenses and gaining a significant foothold before the rallying of South Korean forces or American reinforcements. North Korea would presumably try to leverage its quantitative advantage of troop strength against the perceived superior technological capabilities of South Korean and US forces.

A major threat of a Korean conflict is the bombardment of the South Korean capital of Seoul, which is one of the world's largest cities and has nearly forty percent of the country's population living within forty miles of it. With an artillery force of over 12,000 self-propelled and towed weapon systems, though outdated and with limited range, the country could "sustain up to 500,000 rounds an hour against Combined Forces Command defenses for several hours." Short-range attacks with nuclear, chemical, or biological warheads are also possible for crossing the Demilitarized Zone or attacks against Seoul, with initial casualties in the thousands.^[5]

There is much debate, however, over how far North Korean forces could progress south or whether they could sustain a prolonged offensive against South Korean and American forces, especially with the latter's presumed air and naval superiority.^[6] Most allied plans do not assume that North Korea could successfully consolidate gains around Seoul or breaks along the Demilitarized Zone.

Risk analysis consulting firm Country Risk Solutions has provided four possible conflict scenarios:

• a North Korean provocation followed by a South Korean response that spirals into war, bringing in the US and other South Korean allies
• a North Korean blitzkrieg on South Korea similar to the North Korean attack that started the Korean War
• a limited North Korean attack followed by peace overtures
• a North Korean provocation followed by a South Korean response that spirals into war that results in a quagmire

The scenario analysis made assumption that North Korea will not use nuclear weapons, North Korea will not conduct ballistic missile attack against continental US or it's allies, North Korea's attack will not have prior Chinese approval, and China would not intervene on behalf of North Korea and predicts US/SK coalition will not be defeated.^[7]

A paper in the Strategic Studies Quarterly (SSQ) cites several reasons why China would not side with North Korea if North Korea initiated an unprovoked attack on South Korea without prior Chinese approval: today's China has no agenda to promote their political ideology, and economic progress would be harmed from a prolonged war.^[8] This analysis does not discuss regime anarchy, political upheavals, or any other circumstance which would involve humanitarian crises in North Korea.

Espionage

In December 2009, South Korean media reported that North Korean hackers may have stolen secret information from OPLAN 5027 after a South Korean officer used an unsecured USB memory stick on his work computer, violating security regulations.^[9][10]

See also

• OPLAN 5029
• Military of North Korea
• Military of South Korea
• Korean unification

Notes

External links

• OPLAN 5027 Major Theater War - West
• U.S. speeds attack plans for North Korea
• Colin Robinson, Standoff with North Korea, Centre for Defense Information, 2002.