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jams, vol. 14, no. 2

Revisiting the Global Posture Review

A New U.S. Approach to European Defense and NATO in a Post-Ukraine War World

Major Maxwell Stewart, USMC​

https://doi.org/10.21140/mcuj.20231402004

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Abstract: This article revisits the 2021 Global Posture Review’s determination for a status quo European force posture in the wake of the Russian invasion of Ukraine. Considering the poor Russian performance and attrition in the war, and the likely frozen conflict that will emerge, the article lays out the process by which the United States can draw down its permanent presence in Europe to refocus on the Pacific and restructure its relationship with the North Atlantic Treaty Organization (NATO), all while maintaining alliance unity. The article has two main recommendations. The first is a time line for a reduced U.S. force posture in Europe from the present to 2035 while placing more emphasis on a European role in NATO leadership. The second is focused on how to maintain strategic flexibility while reassuring NATO allies of U.S. commitment. It then identifies and provides mitigations for the anticipated risks associated with the recommendations.

Keywords: Europe, Global Force Posture, rebalancing, Russia, Ukraine, dynamic force employment, deterrence, North Atlantic Treaty Organization, NATO

 

Background

In November 2021, the much-anticipated Global Posture Review (GPR), an assessment on the current and desired global U.S. military presence, was finally concluded with underwhelming results. As one source put it, “after a nine-month deep-dive by Defense Department planners and policy experts billed as a holistic look at where and how America is deployed around the world, the Pentagon has concluded that no major changes to its military posture are needed.”1 This largely status-quo assessment included Europe, where the GPR did little more than reverse the controversial Donald J. Trump administration drawdown initiatives on the continent.2

However, the 2022 Russian invasion of Ukraine reinitiated high-level discussions regarding the future of U.S. force posture in Europe. Despite the Joseph R. Biden administration’s 2022 National Defense Strategy, which describes China as the “most consequential strategic competitor and the pacing challenge for the Department [of Defense]” (DOD) and is to be prioritized over Russia, there are voices advocating for an expanded and enduring U.S. presence in Europe.3 During congressional testimony that same year, though, and in the wake of the Russian invasion, Chairman of the Joint Chiefs of Staff (CJCS) General Mark A. Milley indicated the DOD was planning for a future force posture in Europe that might not align with the published strategy, indicating the likelihood of expanding the permanent U.S. force presence in the theater.4 A year later, in March 2023, that became a reality when the U.S. Army established a permanent forward presence of its Fort Knox, Kentucky, based V Corps at Camp Kościuszko, Poland.5

However, some analysts are urging caution. As more U.S. forces head to Europe either permanently or on rotation, “it will get increasingly difficult to pull them out due to external pressure from allies and internal pressure from advocates who believe a larger U.S. military presence on Europe is required, said Rachel Rizzo, a senior fellow at the Atlantic Council’s Europe Center.”6 The United States cannot and should not continue to split its attention between both Europe and the Pacific, especially given the lackluster performance of the Russian army and that forces’ severe attrition during the last year and a half of conflict. With this in mind, the Biden administration should revisit the 2021 GPR decisions made concerning U.S. force posture in Europe, as well as those that have occurred in the wake of the Russian invasion, while taking into account the changing security situation on the continent. What follows is a recommended course of action that capitalizes on the current situation to both fundamentally reshape the United States’ long-term presence in the theater, as well as its relationship to NATO, to ultimately build a more enduring, equitable, and secure transatlantic security architecture.

 

Planning Scenarios

This reassessment of the ideal U.S. force posture in Europe is based on the most likely outcome of the current Ukraine-Russia War, identified as the “frozen conflict” scenario. However, other considered war-termination scenarios are also listed below for context and consideration.

Frozen conflict: In this scenario, both Russian and Ukrainian forces exhaust their offensive capacity along a settled “line of control” somewhere in eastern Ukraine. Various cease-fires are negotiated but unenforced and broken regularly. Diplomatic negotiations continue but bear little fruit. In a best-case scenario, this resembles the “new normal” in eastern Ukraine that was achieved after the 2014 invasion. In the worst-case scenario, it resembles the Korean War’s “stalemate” phase from 1951 to 1953 in which both sides, knowing that negotiations were ongoing, conducted limited offensive operations to seize advantageous terrain to solidify new territorial claims at the conflict’s termination.7

Escalation to conventional NATO-Russia conflict: This would likely not be from a direct attack by Russia on NATO, or NATO against Russia, but rather via escalation from miscalculation or accidental engagement. The force posture in response to a direct NATO-Russia conflict is outside the scope and classification of this policy recommendation and will be directed via the execution of the appropriate NATO/European Command (EUCOM) war plans. These plans doctrinally include the detailed planning “necessary to determine force deployment, employment, sustainment, and redeployment requirements.”8

Russian regime collapse: Despite the belief at the outset of the conflict that military failure, in combination with economic sanctions, could lead to the end of the Vladimir Putin reign in Russia, that scenario has become less likely. Instead, the world has seen the Russian political and media elite double down on their support for the invasion and see themselves as victims in a necessary war against the West. Even if the recent short-lived Wagner Group mutiny launched by Yevgeny Prigozhin had succeeded and the mercenary chief had arrested his rivals in the Ministry of Defence, there is little indication that it would have caused an end of hostilities in Ukraine. As the Wilson Center published last year:

With the widespread blindness of the populace with respect to the actions of the Russian ruling elites, a blackout on real information, and the fear of consequences of dissent, the political system remains strong: Putin has learned from the late-Soviet experience that any weakening of a repressive stance, any letting up on the propaganda machine, spells the end of an autocracy. . . . The absence of powerful alternative regional elites to take up the reins of governance puts “paid in advance” to any notions of dismantling Putin’s regime. And trust in Vladimir Putin personally remains high in all the regions.9

 

Nuclear escalation: The most likely scenario in which nuclear weapons are used is a Russian attempt to “escalate to de-escalate.” In this instance, they would utilize a low yield tactical nuclear weapon on the battlefield to force a cessation of hostilities for fear of vertical escalation. If this attack were met in response by NATO tactical nuclear strikes, it is not inconceivable that the tit-for-tat strikes could result in the strategic nuclear arsenals of both sides being deployed against one another’s homeland. The long-term outcome of this scenario is not only horrible, but impossible to accurately plan for and outside the scope of this policy recommendation.

 

Recommendation

As a result of the significant attrition to Russian forces and the likely “frozen conflict” scenario, the United States should utilize European and NATO confidence to reduce its existing force posture in Europe during the next decade, while maintaining the strategic flexibility to rapidly redeploy forces to the theater in the event of crisis and maintain the DOD infrastructure required for contingencies.

 

Line of Effort 1: Reposture for a New Normal

Line of Operations 1: Immediate Response (Remainder of 2023)

The intent of this line of operation is to initiate the drawdown of U.S. forces deployed in response to the current crisis and return to the status quo force posture. There are 65,000 troops normally stationed in Europe, with 10,000–15,000 additional troops that rotate through annually, bringing the normal number to 80,000. That figure has swelled to more than 100,000 troops in response to the invasion, the most since 2005.10 These initial surge forces were critical to establish deterrence and reassure American allies immediately following the invasion as U.S. forces generally maintain higher levels of readiness and ability to deploy than their NATO counterparts. However, as early as April 2022, NATO had mobilized and deployed up to 40,000 troops to its shared border with Russia, a massive increase in the 4,000 personnel “tripwire force” that previously existed in the Baltics.11 Even still, more than a year after the initial invasion, the United States has maintained its expanded presence in Europe.12 The successful mobilization of the NATO militaries along their eastern flank, in addition to the accession of Finland (and soon Sweden) into the alliance, as well as the severe and long lasting degradation of Russian conventional offensive capacity, should set conditions for the 20,000 U.S. forces deployed in response to the crisis to be returned home to rebuild their readiness in preparation for follow-on contingencies.

 

Line of Operations 2: Creating a New Normal (2024–2029)

The creation of a new normal would occur during the next five years and capitalize on the period before which the Russian military industrial complex can regenerate new offensive conventional capacity.13 This is the time frame in which NATO countries who have promised to increase defense spending and expand their militaries in the wake of the invasion will likely begin fielding these new forces.14 These expanding NATO militaries will enable a limited drawdown of permanently stationed U.S. forces in Europe. This would not mimic the hasty, ill-conceived, and impromptu Trump administration planned withdrawal of 12,000 troops that at the time was called “sudden and dangerous” by the Council on Foreign Relations. Unlike that decision, taken without the consultation of NATO allies, this would be conducted as an iterative process done in consultation with other NATO members.15 That is not to say they would not be hesitant to see U.S. troops leave, but they would be actively part of the process to identify the requisite force needed to stay.

The intent would be to leave a smaller force in Europe with a more narrowly scoped but still decisive mission. The current U.S. force posture in Europe is one in which the United States provides the bulk of an all-domain deterrence force against Russia. The new posture would create a force built around blunting Russian aggression and surging forces into theater should a conflict begin again. This means forward deploying combat credible forces capable of rapidly transitioning from training to real-world operations predominately in the eastern portion of NATO. Forward posturing forces in Eastern Europe would free up certain intratheater movement aviation platforms to be redeployed to the Pacific. The new European posture should also primarily be land and air forces, as the land is the decisive domain in which a European conflict would be decided. NATO member naval forces would be primarily responsible for the maritime fight, allowing U.S. ships to be permanently repositioned to the Pacific as well.

 

Line of Operations 3: Alliance Reimagined (2029–2035)

The remainder of the decade and the first half of the 2030s would allow for this force posture to be modified to meet the needs of the environment with modest rebalancing to achieve an optimized topline U.S. force number in Europe. Once this is solidified, the focus should then shift to institutional reforms in NATO. Currently, the Supreme Allied Commander Europe (SACEUR) is always an American general officer while the NATO secretary general is always a European. The alliance should develop a rotation that allows SACEUR to be a European officer with their deputy position filled by an American as well as an American filling the role of the secretary general.16 This would serve to ensure that the newfound confidence and sense of burden sharing in the European NATO allies does not dissipate after the current crisis. While there are always concerns about the placement of U.S. troops under the operational control of foreign officers, it has happened many times in the past.17 Allowing for a European SACEUR and American secretary general would truly place the emphasis for European defense on the shoulders of Europe, while also maintaining a credible and enduring U.S. commitment.

 

Line of Effort: Posture for Contingencies

Line of Operations 4: Preserving Strategic Flexibility

To preserve strategic flexibility, the United States should keep the current infrastructure, or as necessary develop new infrastructure in Europe to allow it to surge forces back into the theater. This would include prepositioned stockpiles of weapons, vehicles, and ammunition. These weapons and vehicles allow U.S. forces to fall in on assets in theater after a conflict begins, reducing the requirement to float or fly large formations oversees. These prepositioned stockpiles could either be expansions of the existing sites or the development of new ones, ideally near highways or rail heads. To enable this intratheater movement, DOD can develop new contracts with regional heavy lift companies to ensure logistical support for the larger projected formations that will flow into Europe during a crisis.

Furthermore, the United States and European allies should invest in developing additional military-use airfield and port infrastructure to enable what is called joint reception, staging, onward movement, and integration (JRSOI).18 Finally, NATO should streamline administrative requirements for movement, as “within Europe, virtually any movement of U.S. or allied forces requires crossing multiple borders of sovereign nations. Border crossings require customs processes, diplomatic clearances, route approvals, timing, and escorts, which vary widely amongst European nations.”19 Simplifying this process before a crisis is imperative to ensure the United States’ ability to rapidly redeploy large formations to theater is credible.

 

Line of Operations 5: Assuring NATO

To continue to assure NATO and demonstrate enduring U.S. resolve and commitment to the alliance, the United States should maintain the current average of 10,000–15,000 U.S. troops, primarily from ground combat formations, on rotational deployments to Europe annually.20 This will not only benefit the alliance, but it will continue to provide certain enduring advantages to continental United States (CONUS)-based units. These advantages include the opportunity to gain firsthand knowledge of the terrain of the likely conflict zone, practice at deploying to Europe, and the maintenance of critical interpersonal relationships between U.S. and European commanders at the tactical level. This last aspect is key and critical to true interoperability.

Additionally, the United States should also conduct episodic dynamic force employment (DFE) rotations through EUCOM with bomber task forces, armored brigade combat teams, Marine Air-Ground Task Forces, or other elements of the Joint force. DFEs are meant to allow the United States to be “strategically predictable, but operationally unpredictable.”21 Unlike normal rotational deployments that are planned years in advance, DFEs are conducted on short notice specifically to demonstrate the agility and responsiveness of U.S. forces and to complicate adversary decision-making.

Finally, the United States and its NATO allies should conduct more large-scale exercises on the continent, demonstrating the credible ability to field the large formations required to fight and win during conflict. In recent years, the Defender Europe series of exercises have grown in scope and complexity, with Defender 23 including 17,000 NATO troops from 26 nations. This included the deployment of more than 9,000 CONUS-based U.S. troops and 7,000 pieces of CONUS-based equipment for the multimonth exercise, with an additional 13,000 pieces of equipment drawn from prepositioned forward stockpiles.22 As the U.S. permanent presence in Europe decreases, its contribution to these types of large-scale exercises should increase in a commensurate fashion. The eventual goal should be the deployment of tens of thousands of U.S. troops to Europe for short duration multinational NATO exercises, utilizing and validating the JRSOI infrastructure investments, and serving as operational rehearsals before returning these forces back to their CONUS home stations.

 

Justifications

China’s People’s Liberation Army (PLA) has been and continues to rapidly expand its capabilities in the Western Pacific: “The Chinese Navy is already acknowledged as being larger than its American counterpart . . . [and] has also spent two decades investing in anti-access/area-denial weapons to push both the American Navy and Air Force back far from its shores.”23 The former Indo-Pacific Command (INDOPACOM) commander, Admiral Philip S. Davidson, shocked the members of the Senate Armed Services Committee when he stated in 2021 that China may seek to reunify with Taiwan in the next six years. The newfound confidence of the NATO allies and their increased defense spending provides the United States the opportunity to shift forces to the Indo-Pacific during the period of strategic vulnerability from now until 2027, aptly titled the “Davidson Window.”24

Furthermore, there is a need to reassure allies and partners in the region. The Biden administration has already taken steps toward this goal, including high-profile visits and consultations with Pacific partners. However, these must also be backed up by a credible military posture in the region. The Ukraine crisis has stiffened the resolve of some Indo-Pacific allies and partners, specifically South Korea, Australia, and Japan; with Japan increasing its defense spending, reinvigorating its defense industrial base, purchasing offensive precision strike weapons, and debating amending its own pseudo-pacifist constitution.25 The United States should exploit this by reinvigorating status of forces agreements with these countries and others such as the Philippines and Singapore, to expand access, basing, and overflight rights.

A force reposturing of combat credible air, naval, and reconnaissance forces from Europe to the Indo-Pacific is also critical to avoiding a Chinese fait accompli against Taiwan or other regional targets. A fait accompli is defined as something “accomplished and presumably irreversible.”26 In a military sense, this is

a tactic designed to deter external intervention. . . . By rapidly changing facts on the ground, the aggressor could achieve its territorial goal before any third party could intervene. Once faced with an accomplished fact, third parties could only intervene by attempting to roll back the aggressor’s territorial gains, which usually demands the use of force. Since using force is costly and risky, third parties are less likely to intervene after the fait accompli had already occurred.27

 

The placement of these forces complicates the People’s Republic of China’s (PRC) desire for a short and decisive fait accompli against Taiwan—or any other objective—and risks the potential lengthening of a conflict. This introduces the possibility that the United States and its allies and partners would have the time required to muster a sufficient force to intervene and/or develop the international consensus required to levy devastating sanctions.

There is also the enduring and unavoidable risk of crisis erupting on the Korean Peninsula. Despite the sometimes-singular focus on China among senior U.S. decision-makers, North Korea remains a disruptive and potentially dangerous actor in the Indo-Pacific. With the arrival of the more conservative Yoon Suk Yeol administration in Seoul, there has been a distinct uptick in bellicose rhetoric coming from either side of the border. In April 2022, after the South Korean defense minister boasted of the ability to hit any target in North Korea with ballistic weapons, the north released a statement threatening to use nuclear weapons in retaliation. Any miscalculation or unintended escalation on the Korean Peninsula could have disastrous consequences throughout the region. Even if Kim Jong Un’s nascent nuclear weapons arsenal was not used in a conflict, his regime still maintains the conventional capability to devastate large parts of South Korea. The capital of Seoul sits within range of more than 5,700 North Korean artillery pieces across the border, estimated to be capable of inflicting more than 200,000 casualties in the first hour of any conflict.29 While there is already a credible U.S. force permanently stationed in South Korea, the reallocation of troops from Europe to posture against this threat increases deterrence and reduces the time required to respond to crisis with decisive force.

 

Risk and Risk Mitigation

Risk #1

The primary risk incurred with this reposturing of U.S. forces out of Europe during the next decade is the emboldening of Russia to attempt another opportunist military move in Eastern Europe. While the Russian military has taken significant loses in the current conflict, it is conceivable that over time it will be able to rebuild its military via a combination of conscription, easing of sanctions, and support from China. There is also the possibility that the intense sanctions against the Russian people, in combination with the West’s contribution to mounting Russian casualties, will develop a desire for revenge among the Russian population. The withdrawal of U.S. troops during the next decade could send the message of a lack of commitment to the NATO alliance and Europe. With a newly rebuilt military, the lessons learned during their experience in Ukraine, and an angry populace at home, the Russians could look for a face-saving opportunity to strike back against the West.

 

Mitigation for Risk #1

This risk can and will be mitigated through a combination of military and economic means. Militarily, the continued rotation of U.S. troops to the eastern flank of NATO will serve as a demonstration of the continued American commitment to the alliance. While the overall force structure may decrease, this deployment of combat credible formations to the most likely areas in which conflict would occur codifies the U.S. willingness to fight alongside its allies during crisis. Furthermore, the various DFEs and large-scale exercises will induce doubt in the minds of Russian decision-makers that they could achieve a quick victory before the United States could deploy a decisive war-winning force from CONUS. Finally, while it is unlikely that all of the current economic sanctions against Russia will continue in perpetuity during a frozen conflict scenario, some certainly will. It is recommended that the sanctions that most drastically impact the Russian people are gradually lifted over time in an attempt to reconnect them to the global community and avoid an extended feeling of victimization that could lead to demands for revenge. However, those sanctions currently in place targeting the Russian defense industrial base should remain and, where possible, expand to slow or stop Russia’s ability to rebuild its military post conflict.30

 

Risk #2

The second major risk is a loss of U.S. leadership in NATO during the next decade. This risk can manifest itself in several ways. The first is an appearance of a reduced U.S. interest to NATO, which could drive the European member states to question the commitment of their transatlantic ally. The second could be a hit to U.S. weapons exports if NATO member states expand their own domestic industrial base and increase their exports on the continent. This would be a major hit to U.S. defense firms who, from 2016 to 2020, sold $51.3 billion in arms to NATO countries.31 The final way this risk could manifest itself would be a European-led NATO alliance taking unwanted military action contrary to U.S. strategic goals. Until now, all NATO use-of-force operations have been U.S.-led and supported to include Bosnia, Kosovo, Libya, and Afghanistan. Debates have existed for years to determine what type of out-of-region operations, if any, NATO should conduct.32 In the most extreme circumstances, the risk exists that a European led NATO could result in a Suez Canal-type crisis moment in which the United States found itself fundamentally at odds with a military action taken by its allies.

 

Mitigation for Risk #2

This risk can be mitigated by developing an official or unofficial rotation requiring the deputy SACEUR and NATO secretary general to be Americans when the SACEUR is European. The absence of an American SACEUR does not need to mean a commensurate absence of U.S. leadership. The United States can continue to drive NATO initiatives and actively avoid the creation of a power vacuum in the alliance. Even after a decade-long partial drawdown in Europe, the United States will still be the largest single contributor to NATO and able to exert significant influence over the alliance. Furthermore, the United States still dominates in certain military capabilities, such as intratheater maritime and air lift as well as cyber and ballistic missile defense, which make it indispensable to the alliance. The United States can simultaneously encourage an increase in European leadership and confidence in NATO, while maintaining its stewardship of the organization.


Endnotes

  1. Andrew Eversden, “Pentagon’s Global Posture Review Emphasizes China, but Lacks Major Strategic Changes,” Breaking Defense, 29 November 2021.
  2. Jim Garamone, “Biden Approves Global Posture Review Recommendations,” DOD News, 29 November 2021.
  3. “Fact Sheet: 2022 National Defense Strategy,” Department of Defense, 28 March 2022.
  4. Dan Lamothe, “As Ukraine War Drags on, Pentagon Makes Long-Term Plans for Europe,” Washington Post, 5 April 2022.
  5. Devin Klecan, “First Permanently Assigned U.S. Soldiers Arrive in Poland,” U.S. Army, 8 March 2023.
  6. Lamothe, “As Ukraine War Drags On.”
  7. Allan R. Millett, “The Korean War,” Britannica, accessed 27 July 2023.
  8. Joint Planning, Joint Publication 5-0 (Washington, DC: Joint Chiefs of Staff, 2020), I-12.
  9. Vadym Denysenko and Andrian Prokip, “The Failure of Putinism: A Quick Collapse or a Slow Downfall?,” Wilson Center, 5 April 2022.
  10. John Vandiver, “US Has 100,000 Troops in Europe for First Time Since 2005,” Stars and Stripes, 15 March 2022.
  11. Joshua Zitser, “NATO Will Deploy a Permanent Full-Scale Military Force on Its Border with Russia to Combat a Future Invasion, Alliance’s Chief Says,” Business Insider, 10 April 2022.
  12. Meghann Myers, “New in 2023: US Troops in Europe to Continue Deployments, Training,” Military Times, 30 December 2022.
  13. Joe Saballa, “Russian Military May Take 10 Years to Recover from Ukraine War: US Intel,” Defense Post, 5 May 2023.
  14. Howard Brad, “Russia’s Invasion of Ukraine Could Spark a NATO Defense Spending Spree,” CNBC News, 1 April 2022.
  15. Philip Gordon, “Trump’s Sudden and Dangerous Troop Withdrawal from Germany,” Council on Foreign Relations, 8 June 2020.
  16. Ian Davis, “How About a European for SACEUR This Time, You Guys?,” NATO Watch, accessed 27 July 2023.
  17. Davis, “How About a European for SACEUR This Time, You Guys?”
  18. LtGen Stephen Twitty, “Logistics Important to Shaping the European Theater,” U.S. Army, 4 November 2019.
  19. Twitty, “Logistics Important to Shaping the European Theater.”
  20. Vandiver, “US Has 100,000 Troops in Europe.”
  21. Tyson Wetzel, “Dynamic Force Employment: A Vital Tool in Winning Strategic Global Competition,” Real Clear Defense, 18 September 2018.
  22. Todd Lopez, “Multinational Exercise Defender 23 Kicks Off This Month in Europe,” DOD News, 5 April 2023.
  23. Jerry Hendrix, “Closing the Davidson Window,” Real Clear Defense, 3 July 2021.
  24. Hendrix, “Closing the Davidson Window.”
  25. Anthony Kuhn, “Eying China, Japan Lifts Longtime Restrictions to Allow Major Defense Buildup,” National Public Radio, 16 December 2022.
  26. “Fait Accompli,” Merriam-Webster, accessed 27 July 2023.
  27. Lan Ngo, “South China Sea: Deterring a Fait Accompli,” National Interest, 12 March 2019.
  28. Josh Smith, “North Korea Says It Will Strike with Nuclear Weapons if South Attacks,” Reuters News, 5 April 2022.
  29. Lee Haye-ah, “N.K. Artillery Attack on S. Korea Could Cause More than 200,000 Casualties: U.S. Think Tank,” Yonhap News Agency, 8 August 2020.
  30. Joe Gould, “New US Sanctions Target Russia’s Multibillion-Dollar Defense Sector,” Defense News, 2 March 2022.
  31. “US Arms Exports,” Campaign Against Arms Trade, 3 June 2021.
  32. Ivo Daalder, “NATO, the UN, and the Use of Force,” Brookings, 1 March 1999. 

About the Author

Maj Maxwell Stewart is a combat engineer officer and northeast Asia regional area officer. He recently completed a three-year tour as an action officer in Operations Division, Plans, Policies and Operations, Headquarters Marine Corps. He holds a master’s degree in security policy studies from the George Washington University’s Elliot School of International Affairs. These views are presented in a personal capacity and do not necessarily reflect the official views of any U.S. government department or agency.

https://orcid.org/0009-0009-2150-1190

The views expressed in this article are solely those of the author. They do not necessarily reflect the opinions of Marine Corps University, the U.S. Marine Corps, the Department of the Navy, or the U.S. government.

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