Options to Penetrate Adversary Anti Access / Area Denial (A2/AD) Systems

Major Jeffrey Day is a Royal Canadian Engineer officer currently attending the United States Army School of Advanced Military Studies. He can be found on Twitter @JeffDay27. Divergent Options’ content does not contain information of an official nature nor does the content represent the official position of any government, any organization, or any group.

National Security Situation:  U.S. military Multi Domain Operations (MDO) to Penetrate adversary Anti Access / Area Denial (A2/AD) Systems.

Date Originally Written:  February 27, 2020.

Date Originally Published:  March 20, 2020.

Author and / or Article Point of View:  This article is written from the point of view of the United States military.

Background:  U.S. Army Field Manual 3-0, Operations warns of the potential for near-peer or great power conflict against adversaries who can compete and oppose the United States in all domains and achieve relative advantage either regionally or worldwide[1].  On the other hand, TRADOC Pamphlet 525-3-1 The United States Army in Multi-Domain Operations 2028 implies that if competition and deterrence fail, the Joint Force quickly penetrates and disintegrates (A2/AD) systems and exploits the resulting freedom in order to win[2]. The MDO concept at this time does not include a shaping phase. Field Manual 3-0 describes how “Global Operations to Shape” continue through the joint phases of conflict, but the tasks listed are passive[3].

Significance:  There is a contradiction between these two U.S. Army concepts. If an enemy can compete and oppose the United States across all domains, quickly penetrating and disintegrating the enemy’s A2/AD would be at best extremely costly in resources, effort, and lives, and at worst impossible. The U.S. military relies on having a position of relative advantage in an area which it can exploit to create the conditions to be able to penetrate and disintegrate enemy A2/AD. Achieving that position is essential to the successful application of the MDO concept, but the enemy A2/AD systems can post a threat to U.S. forces and maneuver hundreds of miles from their borders.

Option #1:  The U.S. military conducts shaping operations in the peripheries, exploiting the enemy’s vulnerabilities throughout the global maneuver space, to indirectly weaken A2/AD systems.

The Second World War has several examples of the belligerents exercising this option. Prior to D-Day, the Allies limited German access to weather information through the Greenland campaign. Weather intelligence from Greenland was extremely useful to accurately predict European weather[4]. Rear-Admiral E.H. Smith of the United States Coast Guard organized the Northeast Greenland Sledge Patrol in the fall of 1941. It consisted of Danish and Norwegian trappers and Inuit hired to regularly patrol the East coast of Greenland and report any signs of enemy activity[5]. Through their operations, and other missions, Germany access to quality weather information, and thus their ability to forecast European weather was greatly reduced. U.S. President Eisenhower highlighted the importance of the weather data secured by the Allies and denied to the Axis many years after the war. When President Kennedy asked President Eisenhower why the invasion of Normandy had been successful, Eisenhower’s response was, “Because we had better meteorologists than the Germans![6]” What Eisenhower really meant was that the Allies had better weather data than the Germans, a position of relative advantage which largely came from shaping operations prior to attempting to defeat the Atlantic Wall, which is an historic example of an early A2/AD system. Throughout the history of global war there are campaigns in the peripheries with similar objectives. Examples include Germany attempts to deny British access to middle eastern oil in the Second World War, and the British campaign to secure eastern Indian Ocean sea lines of communication by capturing Madagascar during the Second World War.

Risk:  It took the Allies until 1944 before they set the conditions to attack into northern mainland Europe. U.S. shaping efforts today will also take time, during which the enemy will be able to further prepare their defense or also exploit opportunities in the global maneuver space. Due to their lack of mass, the smaller U.S. forces committed to the peripheries will be vulnerable to an enemy set on retaining their position of advantage.

Gain:  Shaping operations in the peripheries can be useful by:

  • Securing, seizing, or denying access to critical resources
  • Securing, seizing, or denying access to intelligence
  • Defending access to or denying enemy access to strategic lines of communication

By retaining critical capabilities and degrading the enemy’s critical requirements, the United States may be able to force the enemy to rely solely on resources, information, and lines of communication within the enemy’s area of control. If this area of control is continually diminished through the continued execution of peripheral campaigns, the United States will be able to attack in the primary theaters at a time of their choosing and from a position of relative advantage or perhaps even absolute advantage. By weakening the enemy’s A2/AD systems peripherally over a longer period of time, there will be better assessments of their residual capabilities and duration of the weaknesses.

Option #2:  The U.S. military commits resources to ensure technological dominance within specific aspects of domains to permit the Joint Force to quickly penetrates and disintegrates A2/AD.

Through extensive scientific and technical research and development, as well as reliance on technical intelligence to understand the enemies’ capabilities, the United States can ensure that it maintains a position of relative advantage along critical segments of all domains. Option #2 will enable the exploitation of vulnerabilities in enemy A2/AD systems, permitting disruption at key times and locations. Secrecy and operational security will be essential to ensure the enemy is not aware of the U.S. overmatch until it is too late to react.

Risk:  If the enemy is able to counter and minimize the calculated U.S. overmatch through intelligence, superior science, or luck, joint force entry and MDO will fail. It also will be more difficult to assess the impact of actions made to degrade enemy A2/AD systems or the enemy may repair systems before the joint force is able to permanently disintegrate them.

Gain:  This option exploits and does not cede the current technological advantage the United States holds over its competitors. Additionally, it permits the United States to conduct short and decisive operations. Potential enemies will waste resources developing resilient A2/AD systems, with expensive defensive measures protecting all perceived vulnerabilities. To counter these measures, the United States military only has to develop specific specialized capabilities, to penetrate A2/AD at points of their choosing, therefore retaining the initiative.

Other Comments:  None.

Recommendation:  None.


[1] U.S. Department of the Army, Army Doctrine Reference Publication (ADRP) 3-0, Operations. (Washington, DC: Government Printing Office, 2017), 13.

[2] TRADOC Pamphlet 525-3-1 – The United States Army in Multi-Domain Operations 2028, December 6, 2018.

[3] The tasks listed in Field Manual 3-0 are: Promoting and protecting U.S. national interests and influence, building partner capacity and partnerships, recognizing and countering adversary attempts to gain positions of relative advantage, and setting the conditions to win future conflicts

[4] C.L Godske and Bjerknes, V, Dynamic Meteorology and Weather Forecasting (Boston: American Meteorological Society, 1957), 536

[5] David Howarth, The Sledge Patrol (New York, NY: The MacMillan Company, 1960), 13.

[6] “Forecasting D-Day,” NASA Earth Observatory, last modified June 5, 2019, accessed October 27, 2019, https://earthobservatory.nasa.gov/images/145143/forecasting-d-day.

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Options for the U.S. to Deter China in the East & South China Seas

Lieutenant Colonel Christopher Curtin is a Field Artillery Officer with over 20 years of experience in the United States Marine Corps, including at the Pacific Division of Plans, Policies, and Operations at Headquarters Marine Corps.  Annie Kowalewski is a Chinese military and defense researcher at Georgetown’s Center for Security Studies. Divergent Options’ content does not contain information of an official nature nor does the content represent the official position of any government, any organization, or any group.

National Security Situation:  Chinese militarization of artificial islands in disputed waters in the East and South China Seas.

Date Originally Written:  March 1, 2018.

Date Originally Published:  March 12, 2018.

Author and / or Article Point of View:  The authors are a military member and a defense researcher.  The authors believe that Chinese actions in the East and South China Sea are destabilizing and threaten to shift the balance of power in the Asia-Pacific region.

Background:  China is showing no evidence of slowing down its territorial aspirations within the “nine dash line” and continues to emplace anti-aircraft guns and close-in weapons systems on its man-made islands in the East and South China Seas[1].  China also uses its maritime militia to bully neighboring countries and extend Chinese fishing rights and territorial reach.  The United States has thus far been unsuccessful in responding to or deterring these Chinese challenges to the status quo.

Significance:  Chinese actions represent a “salami-slicing” strategy aimed at slowly changing regional norms and asserting Chinese dominance in the East and South China Seas.  This strategy allows China to exert influence and establish itself as a regional hegemon, thereby threatening the balance of power and U.S. primacy in the region.  Chinese militarization and power projection also threaten the United States’ allies and security partners, some of which the United States is bound by treaty to offer security assistance.

Option #1:  The United States invests in capabilities-based deterrents that can deter specific Chinese actions.

Risk:  China has objected to the capabilities that provide this type of deterrent, such as the new F-35B fighter operating on naval vessels in the pacific[2].  China may use the deployment of these capabilities as an excuse to finally militarize islands such as the Scarborough Shoal.

Gain:  A capabilities-based deterrent will make Chinese islands in the East and South China Seas vulnerable and, ultimately, a military liability rather than an advantage.  New technologies such as the F-35B allow the United States more flexibility when operating in the Pacific, by providing U.S. and allied commanders with a 5th generation aircraft that is normally only employed off traditional U.S. aircraft carriers.  Option #1 would not only help offset the eventual Chinese People’s Liberation Army Navy (PLA(N)) numerical superiority in the Pacific, but also demonstrate the U.S. commitment to modernizing a capability that has been historically suited for military operations against static, geographically isolated island targets.  This option may help shift China’s risk calculus when deciding how aggressively it hopes to militarize the islands, once it realizes that increased island investment actually increases vulnerability instead of capability.

Option #2:  The United States invests in strategic deterrence by helping boost allies’ and security partners’ amphibious capabilities.

Risk:  Boosting allies’ and security partner amphibious capabilities runs the risk of antagonizing China.  China has already strongly condemned proposed amendments to the Japanese constitution calling for a larger defense budget[3].  China has been known to use economic and political coercion to pressure regional countries to adopt, or abandon, policies.

Gain:  Boosting allies’ and security partner amphibious capabilities will be key to creating a sea force able to challenge an increasingly capable PLA(N).  This option would also allow allies and security partners to better deal with Chinese salami-slicing activities by providing them with the capability to deter or engage the Chinese on their own, rather than rely on U.S. deployments and assistance[4].

Other Comments:  None.

Recommendation:  None.


[1] Bader, Jeffrey. (2014). The U.S. and China’s Nine-Dash Line: Ending the Ambiguity. Retrieved from https://www.brookings.edu/opinions/the-u-s-and-chinas-nine-dash-line-ending-the-ambiguity/.

[2] Lockheed Martin. (2018). The F-26B Lightning II. Retrieved from https://www.f35.com/about/variants/f35b.

[3] Huang, Kristin. (2017, October 23). China to keep wary watch on Abe’s push to change pacifist constitution. Retreived from http://www.scmp.com/news/china/diplomacy-defence/article/2116635/china-keep-wary-watch-abes-push-change-pacifist.

[4] Erickson, Andrew. (2016, September 21). Seapower and Projection Forces in the South China Sea. Retreived from https://armedservices.house.gov/legislation/hearings/seapower-and-projection-forces-south-china-sea.

A2AD (Anti Access and Area Denial) Allies & Partners Annie Kowalewski China (People's Republic of China) Christopher Curtin Maritime Option Papers South China Sea United States

Anti-Access / Area Denial Options in the South China Sea

Ryan Kort is a Strategic Plans and Policy Officer (Functional Area 59) in the U.S. Army.  He currently serves as the Chief of the Strategy Branch at U.S. Army Africa / Southern European Task Force in Vicenza Italy.  He is on Twitter @kort_ryan36.  Divergent Options’ content does not contain information of an ofﬁcial nature nor does the content represent the ofﬁcial position of any government, any organization, or any group.

National Security Situation:  The People’s Republic of China (PRC) creation of islands and militarization of reclaimed islands in the South China Sea (SCS).

Date Originally Written:  February 9, 2017.

Date Originally Published:  March 9, 2017.

Author and / or Article Point of View:   This article, written from the point of view of a U.S. national security staffer, aims to provide both a collective security and an Anti-Access / Area Denial (A2/AD) deterrent option to the U.S. National Security Advisor.

Background:   The PRC adopted a policy of island building over shallow shoals in the SCS.  The PRC forcibly evicted and continues to harass commercial and naval vessels from other SCS claimants such as the Philippines, Vietnam, and Malaysia through use of fisherman ‘militias’ as naval proxies and other means of gray-zone or ‘hybrid’ warfare[1].  The PRC continues the rapid transformation of many of these semi-submerged reefs into islands replete with hard surface runways for strike aircraft and long-range air defense and fires (both tube and missile) capabilities, which pose an A2/AD threat to any actors the PRC may seek to keep out of its claimed ‘9 dash line’ area[2].  

Signiﬁcance:  Other nations that border the SCS view the PRC’s actions as destabilizing, illegitimate, and threatening to their important national security and economic interests.  Several reclaimed islands are within the Exclusive Economic Zones recognized by the United Nations Convention on the Law of the Seas[3].  The SCS is a critical economic transit route, which approximately 30 percent of all annual maritime trade passes through, including $1.2 Trillion worth of goods destined for U.S. markets[4].  In times of crisis, the People’s Liberation Army, Navy and Airforce could disrupt the free movement of commerce through the area and coerce other nations in the region to recognize PRC dominion over the SCS.

Option #1:  Utilize diplomatic efforts to contain the PRC through the creation of a collective security organization, similar to the now defunct Southeast Asian Treaty Organization also known as SEATO.  This treaty organization would provide a deterrent option aimed at containing PRC adventurism and change PRC strategic calculation on future island building.  

Risk:  The PRC will view this diplomatic effort to isolate their nation as overt containment and respond in a variety of ways with multiple means[5].  At the greatest risk will be those nations the PRC deems vulnerable to coercion that it could peel away from the organization and undermine U.S. legitimacy.  Additionally, this option risks immediate failure if those partners critical to the success of the collective security organization do not join- specifically Australia, the Philippines, Singapore, and Indonesia.  This option also may become obsolete if the PRC completes the construction and garrisoning of the islands it needs to assert complete dominance over the SCS before an alliance to balance against it is in place[6].  

Gain:  The U.S. checks the rise of a regional and potential global peer competitor.  The U.S. stands to gain increased security cooperation and economic ties with the nations in the collective security organization.   

Option #2:  Utilizing a multi-domain concept, the U.S. and select allies create an A2AD challenge for the PRC along both the ‘first’ and ‘second’ island chains in order to negate some of the operational and tactical advantages of PRC bases in the region.  The entire coastline of the PRC is vulnerable to area denial.  A strong foundation of U.S. Army maneuver, fires, and sustainment capabilities would enable the U.S. Navy and U.S. Air Force to operate more effectively within the region, while presenting the additional dilemma of embarked U.S. Marine Expeditionary Forces capable of striking critical facilities.  An archipelagic defense through deterrence by denial would need expanded access to existing bases in Japan, with new footprints in the Philippines, Malaysia and Indonesia[7].  The U.S. could employ a mixture of permanent or rotational forces in the region to demonstrate U.S. capability and resolve.  Additionally, the U.S. must have sufficient forces in the region capable of blockading PRC transit through the Strait of Malacca if required.

Risk:  The key risk associated with this option is vertical and horizontal escalation.  A minor incident could intensify quickly and impact other theaters in the U.S. Pacific Command area of responsibility, such as Korea.  Another risk is loss of or initial refusal to allow access to bases in the nations mentioned earlier, which would unhinge this option.  Additionally, resourcing this A2/AD effort with sufficient forces would commit limited U.S. resources, such as air defense and long-range joint fires, to this single problem set.

Gain:  The U.S. deters conflict through placing PRC assets at risk in both the SCS and across the majority of the Chinese seaboard.  Additionally, this option presents the PRC with a dilemma if it should attempt to utilize hybrid or militia forces due to the increased presence of U.S. and allied forces capable of deterring such ‘hybrid’ aggression at the tactical and operational level.     

Comments:  None.

Recommendation:  None.  


[1]  De Luce, Dan and McLeary, Paul, In South China Sea, a Tougher U.S. Stance, Foreign Policy, 02 October, 2015, accessed 09 February, 2017  http://foreignpolicy.com/2015/10/02/in-south-china-sea-a-tougher-u-s-stance/

[2]   Kennedy, Connor and Erickson, Andrew, (21 April 2016). Model Maritime Militia- Tanmen’s leading role in the Scarborough Shoal Incident,  Center for International Maritime Security (CIMSEC), accessed 06 January, 2017, http://www.andrewerickson.com/2016/04/model-maritime-militia-tanmens-leading-role-in-the-april-2012-scarborough-shoal-incident/

[3]  Office of the Secretary of Defense, Annual Report to Congress on Military and Security Developments Involving the People’s Republic of China, 2016;  page 7

[4]  Corr, Anders, How the US can help the Philippines Counter China’s occupation of Mischief Reef, Forbes Magazine Online, 28 January 2017, accessed 09 February 2017. http://www.forbes.com/sites/anderscorr/2017/01/28/is-war-against-china-justified/#5066ccc774fb

[5]  Lieberthal, Kenneth and Jisi, Wang, Addressing U.S- China Strategic Distrust, March 2012, Brookings Institute.  Washington’s security ties with other nations in the region and other actions viewed by China as efforts to constrain China.

[6]  Office of the Secretary of Defense, Annual Report to Congress on Military and Security Developments Involving the People’s Republic of China, 2016;  Page i

[7]  Krepinevich, Andrew, Foreign Affairs, Volume 94, Number 2,  How to Deter China- The Case for Archipelagic Defense, pp 78-86, March/April 2015  

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