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The defense space strategy of the future must acknowledge the connection of space as a “forward region” of homeland defense similar to that of the emergent Asian nuclear-space powers in the second nuclear age environment.

Enhancing space deterrence thought for nuclear threshold threats (part 3)

A future defense space strategy for the Second Nuclear Age

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Deterrence theory favors status quo powers, not powers unhappy with the limitations put on them by the existing distribution of power and superior weapons in the hands of others.
— Therese Delpech: Nuclear Deterrence in the 21st Century

At one time, our nation may be robustly confident, at another, confused and uncertain. For this reason, the American reputation is always being tested, and we must make constant efforts to protect it. Our reputation ebbs and flows depending on the sacrifices we have recently made-or failed to make—in support of our threats.
— James L. Payne: The American Threat (1981)

Since 9/11, the joint doctrine of the Department of Defense states that the United States armed forces will execute homeland defense “by detecting, deterring, preventing and defeating threats from actors of concern as far forward from the homeland as possible.”[1] As a result of the analysis of the threat posed by North Korean EMP weapons attacking the homeland from space, what conclusions can we draw from the framework regarding our deterrence effectiveness? What implications does that have for our future posture and its part in the defense of the homeland? This final article explores conclusions and implications regarding such a high threshold spacepower crisis and how to adequately posture for it in the future.

Why our deterrence posture has been ineffective in North Korea

For several decades, the United States’ posture for deterrence (nuclear, conventional, and space) has been to make deterrent threats, but not to follow through on them.[2] Those few times in the 1970s that we did respond to aggression on the Korean Peninsula led to the deaths of Americans and South Koreans and was not even proportional, much less aimed at escalation dominance to sustain the status quo. The North Koreans have: engaged in provocative military operations on land, sea, and air since the 1960s; detonated atomic, thermonuclear weapons; tested intercontinental and intermediate range ballistic missiles; and achieved space access capability, despite our government’s deterrent threats to use force if the Kim regime crossed any of those lines.[3] The United States did not want to provoke the North Koreans into a full-scale war on the peninsula, thereby altering the status quo. As a result, the credibility of the United States’ deterrents diminished more and more and North Korea gradually escalated past the acceptable thresholds with no consequences beyond soft economic sanctions. How can we restore our credibility in a nuclear, space-enabled environment?

For several decades, the United States’ posture for deterrence (nuclear, conventional, and space) has been to make deterrent threats, but not to follow through on them.

French analyst Therese Delpech argues that to restore credibility, the US must be willing to follow through on its threats of military force. By restoring will and highlighting the determination of the United States to go to war over North Korea’s provocations and attacks, the deterrent thresholds could be restored.[4] This situation, created by our government’s lack of determination and will over many years, has created a condition where the risks are now much higher and the potential for nuclear use is increased. Due to this lack of action, the United States now must be willing to take more aggressive action to establish effective deterrence. As a result of this environment created by deterrence failure and the acceptance of the graduated shifts in the status quo, can the United States deter North Korea from using nuclear space power projection capability?

Can North Korea be deterred?

Scott D. Sagan asserts that North Korea can and will be deterred from using its nuclear weapons against the United States. He does acknowledge that the non-proliferation regimes and other efforts to prevent the Kim regime from achieving nuclear, missile, and space access capabilities have failed. He concludes that Korea has now become a “deterrence problem” that can be managed.[5] His concern lies more with the United States and South Korea “stumbling into nuclear war” and the use of rhetoric as a threat that could lead the North Koreans to attack.[6] This author disagrees with Sagan’s assessment of a “slow moving Cuban Missile Crisis” or that rhetoric such as “all options remain on the table” is “dangerous,” as Sagan bases his assessment on Kim Jong-un within a rational actor model.[7] He postulates a similarity between a US-Soviet bi-polarity and the relationship between the US and North Korea. He stated in an article in Foreign Affairs in 2017 that Kim Jong-un, as a rational actor, would respond better to diplomacy than overt threats.”[8] In addition, Sagan asserts that if the United States takes the use of force off the table this would create stability.

James Payne provides context with regards to threats in a deterrence environment. Drawing on decades of study and development of deterrence theory, Payne states that rhetoric alone does not constitute a threat. A threat exists instead when an adversary concludes that the enemy, in this case the US, has the “capability and will” to go to war “in designated circumstances.”9 Payne asserts that as the strategic culture and context behind North Korea’s strategic behavior attest, “it doesn’t begin to adequately describe” the “psychological strategy” that he terms a willingness for “suicide in your neighbor’s living room.”[10]

Therese Delpech does not assess that North Korea has been or will be deterred by the threats of the United States. She argues the evidence shows that deterrence has already failed in the context of the North Korean nuclear program as well as the deterrence of violence of any kind: “How is it possible that a country unable to feed its people [has] threatened the lone superpower for decades?”[11] She asserts that the sinking of the South Korean Navy vessel ROKS Cheonan and the attack upon South Korean territory killing 46 people as evidence of “deterrence failure.”[12] Responding to this “clear act of war” with nothing stronger than “soft economic sanctions” precipitated a failure that continues to this day.[13] North Korea, she assesses, has concluded that the United States does not follow through on threats of military action in designated circumstances, and as a result, concludes that “it can lash out again and again without facing serious consequences.”[14] Delpech argues that to reverse this trend the United States must follow through with sufficient force to punish Pyongyang and “prevent any similar—or worse—action in the future.”[15] Former South Korean president Lee Myung-bak agrees: “If we once again tolerate North Korea’s blatant act of violence, then I believe that will not promote, but endanger, the peace and stability in the Korean Peninsula.”[16]

The United States should consider a posture similar to what is recommended in the tiered, tailored framework but with additional damage limitation measures.

These disparate opinions demonstrate that there are no guarantees of deterrence 100 percent of the time. Analysis shows that any purely deterrent posture at these thresholds would not be completely assured. This lack of assurance is due to North Korean strategic culture and posture for pre-emptive strike and its use of force in the conventional arena several times with no consequences. Because of this lack of consensus and the uncertainty that pervades the second nuclear age’s multipolar environment, Payne concludes that the United States’ best option is to hedge against the uncertainty through the understanding of strategic culture in decision making and prepare for deterrence failure. Not to do so and to accept that deterrence can be assured, could lead to “unprecedented catastrophe.”[7]

Posturing for space deterrence in the Second Nuclear Age

At the strategic level, the United States now has the responsibly to acknowledge that North Korea’s ability to launch EMP satellites via FOBS to the United States creates a situation where the risk is not just to the Korean Peninsula, but to the homeland and its critical space infrastructure.

The framework for credible space deterrence appears to link up well with the current theory and concepts of second nuclear age strategic thinkers such as Paul Bracken, Kerry Kartchner, and Keith Payne. Bracken argues for a posture that includes strategists who are willing to “think about the unthinkable,” realize that “the doctrine of mutually assured destruction is completely out of fashion,” and realize that the United States may be “forced into more hazardous approaches.”[18] Kartchner argues that to understand such a diverse group of decision makers requires the use of strategic culture analysis to get into the head of the enemy, especially in circumstances where weapons of mass destruction are involved.[19] Payne argues that as a result of such diverse strategic worldviews in various capitals of potential adversaries, damage limitation capabilities including offensive and defensive options must be part of any future posture.[20]

The United States should consider a posture similar to what is recommended in the tiered, tailored framework but with additional damage limitation measures. Reversing the Tao argues that following analysis of the adversary’s strategic culture and view toward deterrence, an aggressive postured adversary should be counter-postured similarly to provide first-strike stability and vertical escalation dominance.[21] While potentially effective for such a scenario, within a Tier 1 Deterrence situation, such a posture is insufficient to effectively deter space crises at the nuclear thresholds tailored to North Korea’s unique strategic culture. Instead, a posture of offensive space superiority supported by defensive damage limitation measures is the best posture for future deterrence. What could this look like?

First, the defense space strategy of the future must acknowledge the connection of space as a “forward region” of homeland defense similar to that of the emergent Asian nuclear-space powers in the second nuclear age environment. As seen in the former Strategy for Homeland Defense and Civil Support Joint Operating Concept, an active, layered defense strategy for the homeland conceptually includes three regions: forward regions, approaches, and the homeland itself.[22] The space medium is one such forward region of the US homeland and at higher thresholds of escalation in space, such as nuclear use that can reach and directly impact the homeland, any defense space strategy that is linked to homeland defense should acknowledge space as a forward region. This view of space as a forward region is vital in “ensuring the freedom of action, full access and use of capabilities…in space” while having the means of denying that freedom to threatening powers.[23] These layers of defense of the space forward region include detection, deterrence, preventative actions, and defeating threats, “as far forward…as possible.”[24]

Detection is more than the operational task of tracking an inbound weapon. Detection is about ascertaining and staying ahead of an adversary who is developing and testing missiles, FOBS, or EMP satellites capable of a strike on the homeland or critical space infrastructures. What is first required is the use of the tiered, tailored framework to assess the adversary’s strategic calculus and the trends of its weapons programs that could potentially become a deployed or used threat. Once that is accomplished, the next step is to ensure that the detection of the threat is operationally possible. Assessing an adversary’s space posture requires a robust space situational awareness (SSA) capability. As a mission area, the DoD articulates the importance of this capability and has invested in ground-based sensors such as the Space Surveillance Telescope, the C-Band radar, the Space Fence, and recently, the Deep Space Radar.[25] In addition, the Space Surveillance Network, originally designed to track space and missile threats to the United States from the Eisenhower years forward, is now used by the U.S. Strategic Command’s Joint Force Space Component Command.[26] In 2014, the US Air Force launched the newest in-space surveillance system called GSSAP (Geosynchronous Space Situational Awareness Program) to monitor activities in the GEO belt. The assets in GEO are of vital national interest and must be defended.[27] The ability to attribute enemy activities and impending threats to our space infrastructure and homeland at all thresholds is vitally important to prevent surprises at the strategic and operational levels.

It might behoove the United States to consider deploying a mixed deterrent force, tailorable to specific adversaries and threats.

Updates to the National Defense Strategy highlight the importance of active and passive defenses to a credible posture for deterrence.[28] The National Defense Strategy does not specifically state that space infrastructures and nuclear, high-threshold threats by adversaries are included in space deterrence, but its approach does appear to be a good starting point. In the past, there has been no real deterrence capability or capacity in either the 2011 National Security Space Strategy or follow-on guidance documents, such as the Space Protection Strategy. As James Payne suggests, for a true deterrence capability to work, there must be a viable capability that adds to the risk calculus of an enemy. This capability requires a multilevel attack architecture that enables options for vertical escalation across the counterspace spectrum, even in high threshold nuclear environments. As mentioned before, a credible deterrent must include capability, will, determination, and a believable declaratory policy.

Second, offensive deterrent capability is an area where much progress has occurred since the days of the Cold War. Where before, a non-nuclear ASAT option did not exist due to technological limitations, there are numerous programs of record that could be modified in short order.[29] The Standard Missile-3 is a workable option for LEO intercepts, while the Ground-Based Interceptor has a potential range into low-medium Earth orbit for active deterrence roles and missions.

However, depending on the adversary in question, and the need in the second nuclear age for escalation dominance at all thresholds, it might behoove the United States to consider deploying a mixed deterrent force, tailorable to specific adversaries and threats. For example, in the 1960s, the Soviet Union deployed nuclear-tipped FOBS and planned to include “spaceships, satellite fighters and other flying apparatus armed with rockets.”[30] The United States, in response, decided to deploy two obsolete Thor missiles at Johnston Island in the Pacific to serve as nuclear ASAT weapons as a deterrent against the Soviets’ use of these FOBS on the United States.[31] The deployment and reuse of old Thor missiles highlights the determination and will of the US government at the time, as well as the analysis of the threshold level that the Soviets were perceived to require to prevent them from utilizing their FOBS on the homeland. These systems also show that there is precedence for taking a current program of record and modifying it for a new and vital mission set. Whatever the capability needed to deter the use of space attack weapons systems, kinetic or nuclear, must be covered in any space deterrent force for the second nuclear age, especially if these weapons are to be used for active deterrence roles, also called preventive action.

Third is preventive action. In the context of a second nuclear age environment, this can cover a multitude of activities. First, it requires taking the North Korean or Chinese concept of “attack to deter,” otherwise called “active deterrence,” and applying it to the US concept of space deterrence and homeland defense. The reason for this, as suggested in the analysis of North Korean strategic culture, is that part of the reason the United States has been exploited in space is due to our assumption of acceptance of international norms and rules. These assumptions of passive response have led to the exploitation of US vulnerability. Shaping US strategy and posture to be more aggressive, like that of China or North Korea, rather than traditional US methods, could aid escalation dominance and second nuclear age deterrence.

Given the offensive dominant nature of both the space environment and the regional non-peer and peer adversaries of the second nuclear age, preventative action may require a deterrent attack against “mobile warfare” assets such as terrestrial-based KE ASATs or EMP satellites that are deployed into LEO. Should indications and warnings from our overhead reconnaissance satellites, aircraft, or SSA sensors indicate that ground-based space attack assets are about to leave garrison, or a satellite is assessed to be an EMP weapon, preventive strikes may be the only sure means of defending the homeland and its critical space infrastructure from destruction.[32] Such preventive actions would be legitimate, and because the use of nuclear weapons from space is banned by international treaty, any such preventive action could be framed as enforcement of such international norms as well as the inherent right of self-defense by the United States.[33]

Fourth is defeating threats that requires capabilities and the political will to engage and defeat the threat as far away as possible from the U.S. homeland. In some ways, this ties-in with the aforementioned deterrence concept of “attack to deter.” Given a high threshold threat such as an EMP device in orbit, or the launching of a FOBS system toward the United States, there must be an option to intercept such threats prior to its overflight of the homeland or other US territory.


For centuries, international law recognized that nations need not suffer an attack before they can lawfully take action to defend themselves from imminent danger.[34] As the author stated previously, “the United States must adapt the concept of imminent threat to the capabilities and objectives of today’s potential adversaries who do not seek in the near term to attack us using conventional means. Instead, [adversary] strategic and military planners rely on asymmetric means to strike at the US homeland’s space enabled” instruments of national power.[35] The dynamic, complex nature of the second nuclear age, the increasing likelihood of nuclear use, even in space, makes having a credible deterrent force, capable of escalating up to all levels of the space power escalation ladder, a vital piece of any future posture for deterrence. To be capable of deterrence in a Tier 1 Deterrence environment requires the ability for warfighting, possibly even nuclear warfighting, within the medium of space. The implications of not preparing in this way could lead to catastrophe for the United States and its allies.


  1. Joint Publication 3-17, Homeland Defense, I-1.
  2. Therese Delpech, Nuclear Deterrence in the 21st Century (Santa Monica, CA: RAND Corporation, 2012), 105.
  3. Payne, The American Threat, 54.
  4. Delpech, Nuclear Deterrence in the 21st Century, 106.
  5. Sagan, “The Korean Missile Crisis,” 72.
  6. Ibid.
  7. Ibid., 76
  8. Ibid., 78.
  9. Payne, The American Threat, 54.
  10. Bracken, Second Nuclear Age, 2.
  11. Delpech, Nuclear Deterrence in the 21st Century, 102.
  12. Ibid., 105.
  13. Ibid.
  14. Ibid., 103.
  15. Ibid. 106.
  16. Delpech, Nuclear Deterrence in the 21st Century, 106.
  17. Payne, Fallacies of Cold War Deterrence, 194.
  18. Bracken, The Second Nuclear Age, 222.
  19. Beatrice Heuser, “Foreward,” in Strategic Culture and Weapons of Mass Destruction: Culturally Based Insights into Comparative National Security Policymaking, ed. Johnson et al., xi.
  20. Payne, Fallacies of Cold War Deterrence, 187.
  21. Stone, Reversing the Tao, 46.
  22. Department of Defense, Homeland Defense and Civil Support Joint Operating Concept, Version 2.0, 1 October 2007, ES-3.
  23. Joint Publication 3-27, Homeland Defense (Washington, D.C.: Department of Defense, 2013), III-14
  24. DOD, Joint Operating Concept, ES-19.
  25. Mr. Kenneth Rapuano, Statement for the Record to Strategic Forces Subcommittee, House Armed Services Committee Hearing, 115th Cong, 2d sess, 15 March 2018, 9.
  26. David N. Spires, Beyond Horizons: A Half Century of Air Force Space Leadership (Air Force Space Command, 2002), 187.
  27. Mr. Kenneth Rapuano, Statement for the Record, 7.
  28. Department of Defense, Summary of the 2018 National Defense Strategy of the United States: Sharpening the American Military’s Competitive Edge, (Washington, D.C: Government Printing Office, 2018), 6.
  29. Joseph T. Page II, Space Launch Complex 10: Vandenberg’s Cold War National Landmark, (Charleston, SC: History Press, 2016), 64-65.
  30. Page, Space Launch Complex 10, 64.
  31. Ibid., 65.
  32. Stone, Reversing the Tao, 57.
  33. The United Nations Charter, the US Constitution and the Outer Space Treaty of 1967 all support the inherent right of self-defense and the international agreed ban on weapons of mass destruction in space.
  34. Stone, Reversing the Tao, 59.
  35. Ibid.

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