The Golden Dome, Missile Defenses and Deterrence

President Donald Trump has proposed the development and deployment of a comprehensive missile defense shield to protect the continental United States against nuclear attack. The so-called Golden Dome will draw upon advanced technology to provide new systems for intercept of attacking ballistic, hypersonic and cruise missiles and other advanced aerial attacks. The objectives of the system would include space-based interceptors capable of boost-phase intercept; deployment of underlayer and terminal phase intercept capabilities postured to defeat a countervalue attack; and, capabilities to defeat missile attacks prior to launch and in the boost phase.[1] Speaking from the White House on May 19, 2025, President Trump noted that he was “completing the job” that former President Ronald Reagan began in the 1980s with his proposal for the Strategic Defense Initiative, an ambitious plan that the technology of that era was insufficient to fulfill.[2] Although the President expressed the hope that the system could be developed and deployed within three years, experts anticipated a longer time period would be necessary, given the ambitious objectives of the system and the variety of new technologies that would need to be developed and tested under realistic conditions.

As aerospace and other defense contractors line up to take part in early phases of research and development for Golden Dome, there are important questions to be considered. First, how will the missile defense shield play into the more comprehensive U.S. strategy for deterrence of near-peer competitors and others? Second, how might a missile defense affect the national approach to nuclear crisis management and extended deterrence? Third, how will the nuclear warning and command, control and communications (NC3) systems coordinate the management of offensive nuclear force operations with the performance of missile defenses during crises or wartime?

I. The Missile Defense Shield and Deterrence

Deterrence is presumably based on the ability to deny any potential attacker his objectives or to inflict retaliatory punishment unacceptable to the attacker, regardless of the size or character of the attack. During the Cold War and well into the twenty-first century, it was assumed that offensive weapons deployed on intercontinental missiles and heavy bombers in sufficient numbers could overwhelm any strategic antimissile defenses deployed by the United States, Russia or other states. Nuclear deterrence was therefore assumed to rest on the credible threat of unacceptable and unavoidable second strike retaliation by the defender. Arguments raged throughout the Cold War and afterward about “how much was enough” for deterrence, but U.S. and Soviet (and later Russian) political leaders and their principal military advisors came to accept the fact of assured retaliation as the basis of stable deterrence.[3]

Nevertheless, research and development efforts on missile defense continued even after the end of the Cold War, and the U.S. withdrawal from the ABM Treaty of 1972 during the George W. Bush administration was received with disappointment and concern in Moscow. Subsequent deployment by the Barack Obama administration of the European Phased Adaptive Approach (EPAA) for regional missile defense of NATO Europe, based primarily on the Aegis missile defense system ashore and afloat, caused additional complaints from Russia.[4] The existing U.S. Ground-based Midcourse Defense (GMD) system for ballistic missile intercept is the only U.S. system for defense against missile attacks by weapons of intercontinental range. It is based on 44 interceptors located in Alaska and California and has had a mixed record of success in tests carried out by the U.S. Missile Defense Agency. It might deflect limited strikes from North Korea or Iran or another state capable of attacks with small numbers of weapons.

The advanced technologies necessary for space-based missile defense interceptors, compared to those based terrestrially, are still in the early phase of development. If these interceptors are to be based in low earth orbit, they will have to be able to defend themselves from space or earth-based attackers. The orbital mechanics of space-based interceptors in LEO will also require many thousands of interceptors in order to defeat even light attacks. For example: CBO’s notional constellation consists of 7,800 satellites in nearly polar LEO costing about $720 billion to develop, deploy, and maintain for 20 years, and an additional $1 billion annually to operate.[5] This constellation was sized to engage nearly 10 simultaneously launched ICBMs during their boost phase.

The other layers of a proposed Golden Dome system are based on existing or imminent defense interceptors. An Upper Wide-Area Surface Layer would include three fields of interceptor silos: the existing field at Fort Greely, Alaska, with ground-based interceptors (GBIs); and two new fields with Next-Generation interceptors (NGIs). These GBIs and NGIs are designed to intercept ICBMs in the midcourse of part of their flight. A Lower Wide-Area Surface Layer would include four Aegis Ashore facilities similar to those already deployed in Poland and Romania, based on Standard Missiles, presumably the SM-3 Block IIA. This missile has a demonstrated capability against ICBMs and shorter-range ballistic missiles. Finally, the Surface-Based Regional Sector Layer of Golden Dome would provide terminal defenses against ballistic and hypersonic missiles in addition to cruise missiles and other airborne threats. CBO’s notional system would include 35 regional sectors, each capable of defending about 270,000 square kilometers. The estimated costs for the Upper Wide-Area site, Lower Wide-Area Site, and Regional Sectors are: 46 billion; 29 billion; and 187 billion, respectively.[6]

The deployment of a Golden Dome system to protect the entire North American continent would, if uncontested, provide for the U.S. a nullification of both Russian and Chinese long-range nuclear forces. If the U.S. system could defeat a Russian or Chinese nuclear first strike, then it presumably could also nullify Russian or Chinese second-strike capabilities. This would undermine the basis of stable deterrence and almost certainly encourage both Russia and China to develop their own advanced missile defense systems and to modernize and increase the sizes of their current strategic retaliatory forces. An accelerated nuclear arms race is a conceivable outcome in this scenario, with newer generations of offenses chasing advanced defenses and vice versa. Following the example of Golden Dome, Russian and Chinese systems would also have space-based as well as terrestrial layers of defense protection, requiring the deployment of antisatellite and defensive satellite weapons (ASATs and DSATs) by all sides. Absent any development of an agreed arms control regime for space-based military assets, a potlatch of heavenly competition in satellites for inspecting, tracking, and if necessary, destroying another state’s satellites is almost inevitable.

II. Crisis Management and Extended Deterrence

Nuclear crisis management has been studied extensively since the Cuban missile crisis of 1962, but thankfully for civilization, the number of these close calls in U.S. – Soviet and then U.S. – Russian relations has not been as large as some pessimists feared. On the other hand, this is not a reason for complacency. The Cuban missile crisis and other dustups in which the possibility of nuclear first use or first strike was on the table, so to speak, remind us that nuclear crises are more stressful than other decision-making episodes in national security policy. Vladimir Putin’s repeated threats of nuclear first use during the present war between Russia and Ukraine have been dismissed by some as bluffs to deter U.S. and allied NATO conventional military escalation against Russia. But the Joseph Biden administration, although providing considerable security assistance, including long-range strike weapons and vital intelligence, to Ukrainian forces, nevertheless remained mindful that boundary maintenance between counterpunching and overreaction to Russian moves could trip the wire of crossing the nuclear threshold. So long as Russia perceived its prevailing circumstances in battle as generally favorable compared to those of Ukraine, Russia could deny itself the option of nuclear first use (supported by periodic oblique or explicit threats of same).

On the other hand, suppose the Golden Dome spun off regional stepchildren in antimissile defense technology that placed in doubt the effectiveness of Russian short-, medium-, or intermediate-range missiles, or air delivered weapons, in the European theater of operations. Russia’s superior numbers of theater nuclear weapons compared to those of NATO have long been regarded as a mainstay of its deterrent capability against any serious reversal of its fortunes in a large-scale conventional war. Russian military doctrine specifically avers that nuclear use is an option in case of a conventional military attack that places in jeopardy the survival of the Russian regime, presumably to include its territorial integrity. Faced with this possibility of neutralization or erosion of its capability for limited nuclear war, Russia would in all likelihood seek to develop countermeasures, including its own theater defenses and wider varieties of less than strategic offensive forces. China, looking down the barrel at this same scenario of potentially diminishing returns from its short and medium nuclear forces, might also compensate with modernization of its theater offensive and defensive missiles and antimissiles.

Another aspect of the regionalization of Golden Dome spinoffs is the issue of extended deterrence provided by the United States to its European NATO allies. European allies that are outside of the protected envelope of Golden Dome might demand U.S. technology support for deploying their own regional or even national antimissile systems – Extended Dome, so to speak. This might reassure those Europeans who have expressed concerns about the steadfastness of the Trump administration’s commitment to defend European allies against future political coercion or Russian military aggression. One could imagine a Baltic or Scandinavian regional missile defense regime supported by American security and financial assistance, as well as several antimissile upgrades for specific countries ready to participate in bilateral agreements with the U.S. Missile defenses against Russian advanced conventional as well as nuclear missile attacks would also be important symbols of NATO solidarity and European commitment to defense burden sharing.

III. Command and Control

Space experts and technology developers underscore the arrival of the democratization of space, so to speak, or new space. Previously, major powers would deploy high-end satellites in geostationary orbit (GEO) that were beyond the capability of less scientifically advanced or resource-constrained actors. In a new space environment, more players can deploy smaller satellites in large numbers in low earth orbit (LEO), leveraging COTS (commercial off-the-shelf) technologies with comparatively smaller development costs. In addition, small satellite architectures in LEO offer operational resilience by proliferation. Larger numbers of satellites create redundant survivability and raise the cost for opponents who might seek to seriously degrade or deny missions performed by the larger network. Efforts to destroy numerous small satellites by kinetic means could result in the creation of space debris that, in extremis, endangers the viability of LEO for all spacefaring actors. This raises the possibility that future attacks on larger constellations of smaller satellites may emphasize cyber rather than kinetic means. As Captain Luke Stensberg, US Space Force, has noted:

Despite relative simplicity in design, small satellites can scale in numbers to produce constellations that can provide key DPS (Data, Products and Services) to NATO warfighters such as C2, ISR, and more. However, cybersecurity experts are warning that this ease of development, scalability, and operations may encourage potential design shortcuts that bring cybersecurity trade-offs. Interconnectivity and standardization can diminish the obscurity of space systems, which once deterred malicious cyber actors from targeting such historically foreign systems.[7]

In addition, NATO considers space as having four segments: ground, user, link and space. In the case of large constellations of satellites deployed in LEO, these satellites will require an expensive global network of ground stations. Satellites in GEO remain relatively stationary with respect to any given point on the surface of the earth. On the other hand, satellites in LEO move at higher velocities in lower orbits and may move in and out of view in less than fifteen minutes.[8] The numerous ground stations also provide additional points of potential cyber vulnerability to malicious attackers.

Apart from technology, another issue with respect to command and control involves the U.S. National Command Authority and its decision premises with respect to activation of the Golden Dome. Traditionally, it has been assumed that only the American President can authorize the first or retaliatory use of nuclear weapons. Presumably, if time permitted, the President would consult with members of the National Security Council and ranking leaders in the military chain of command. In the latter case, the wartime military chain of command goes from the President to the Secretary of Defense (with a dotted line to the Joint Chiefs of Staff) and then to the Combatant Commanders of the various unified and specified commanders (in case of possible nuclear attack, the COCOMs of USSTRATCOM, NORTHCOM and NORAD).

On the other hand, the activation of Golden Dome space-based weapons against nuclear ballistic missile attacks would, in all likelihood, involve the use of non-nuclear weapons (kinetic or otherwise) in defense against a presumed nuclear or other massive attack on the United States and-or its allies. Especially if the attack involved large numbers of hypersonic weapons, allowing little time for deliberation and decision, the activation of Golden Dome might not require as extensive an involvement of political and military principals as would the authorization for an American nuclear response to attack. Protocols could be established within the software of an advanced AI system for warning and attack assessment that, under certain exigent circumstances, anticipated Presidential authorization for the use of non-nuclear strategic defensive weapons against large-scale attacks on the American homeland and-or its allies.[9] The “delegation” or automation of strategic defensive response in this fashion would have to be sufficiently nuanced beyond a simple “yes” or “no” decision so that policy makers and military advisors had a menu of options from which to choose, depending on circumstances. More controversially, some experts have also suggested that AI-enhanced decision procedures for nuclear retaliation should also be implemented in order to increase the surety and credibility of U.S. strategic nuclear deterrence.[10] The head of U.S. Army Space and Missile Defense Command anticipates that future AI-enabled drone and missile defenses may have to be accurate enough and sufficiently trustworthy to take out large numbers of drone and missile attackers by auto-selection without involving a human.[11]

Another aspect of command and control decision making that relates to the possibility of a nationwide antimissile defense system is the likelihood that even a less than perfect missile defense system is still useful in some respects. First, during a process of nuclear crisis management, decision makers may be less anxious to opt for prompt launch or launch on warning if they have high confidence that at least some significant number of attackers will be intercepted before arriving at their intended targets. Second, and related to the first point, the presence of a missile defense system complicates the process of estimation by the attacker as to the actual outcome of any first strike. Deterrence is stronger if the attacker’s calculation of estimates is more uncertain compared to the expectations of the defender. Third, and somewhat ironically, if both the prospective attacker and the defender have deployed national missile defense systems of plausible effectiveness against large scale attacks, the calculations of expected loss from any nuclear exchange become exponentially more difficult. Both sides must reliably estimate not only their own offenses and defenses in terms of their probable performance under exigent (and unprecedented) conditions, but also those of the opponent.

IV. Modelling Offenses and Defenses

The preceding discussion challenges planners and military theorists to consider the interaction between newer generations of strategic nuclear offenses and antimissile defenses. The following is an admittedly oversimplified exercise in doing just that. First, we generate hypothetical but not unreasonable strategic nuclear forces for future U.S., Russian and Chinese deployments in the early to mid-2030s, say 2032 – 2035. Second, we compare the second-strike capabilities of each force relative to that of its opponent in three scenarios: the U.S. versus Russia; China versus the U.S.; and Russia versus China. Third, we calculate the effect of defenses of variable capability on the outcomes of the second step, as noted. Effectiveness of defenses against second strike offenses is measured on a scale: Level I defenses successfully intercept or otherwise deflect at least 20 per cent of the retaliators; Level II defenses at least 40 per cent; Level III defenses at least 60 per cent; and Level IV defenses at least eighty per cent. The results of these estimates are summarized in Charts One through Six, following below. For the sake of discussion and consistency, we assume that each state deploys forces that remain within the limits of the recently expired New START guidelines for numbers of operationally deployed weapons and launchers.[12]

Chart One: Russia – United States
Surviving and Retaliating Warheads

Chart Two: Russia – United States
Surviving and Retaliating Warheads vs. Defenses

Chart Three: China – U.S.
Surviving and Retaliating Warheads

Chart Four: China – U.S.
Surviving and Retaliating Forces vs. Defenses

Chart Five: Russia – China
Surviving and Retaliating Warheads

Chart Six: Russia – China
Surviving and Retaliating Warheads vs. Defenses

Source: Charts One – Six are author’s estimates, based on a model first developed by Dr. James J. Tritten and subsequently modified by the author. For additional information, see Stephen J. Cimbala, War Games: US-Russian Relations and Nuclear Arms Control (Boulder, Colorado: Lynne Rienner Publishers, 2017), Appendix One, pp. 241-243

The data summarized in Charts One through Six show that, if offenses are constrained to New START or comparable levels, then antimissile defenses could impose significant attrition against second strike forces. Therefore, to the extent that deterrence rests on the assumption of assured retaliation, defenses could weaken confidence in deterrence and stimulate additional offensive force building. On the other hand, defenses could also reduce the confidence of putative first-strikers in their attempt to preemptively disarm their opponents’ second-strike capabilities. For this purpose, it might be preferable to task defenses primarily for the defense of nuclear retaliatory forces instead of entire national territories and populations. A third consideration with regard to ballistic missile defenses is the extent to which defense interceptors are based in space as well as terrestrially. Space-based interceptors will require protection against enemy space- and ground-based attackers by friendly defensive satellites (DSATs) and other means.

V. Conundrums and Continuing Controversies

The arguments about development and-or deployment of Golden Dome leave unresolved a number of related issues that deserve mention. The first of these is the underlying theory of deterrence in which missile defense technologies are embedded. One theory regards a combination of offenses and defenses as the most reliable approach to deterrence. From this standpoint, missile defenses should not be intended to supersede offenses but to support deterrence based on denial as well as on assured retaliation. The second theory aspires to missile defenses that are dominant over competing offenses, gradually leading to a defense-dominant world. A third approach to deterrence would use defenses primarily to protect the strategic nuclear retaliatory forces, i.e., to support deterrence based mainly or solely on assured retaliation. At some point, policy makers and strategic planners will have to choose among these and other competing approaches to deterrence.

A second unresolved issue as U.S. planners move forward with Golden Dome is how geographically and politically inclusive it will be. For example: in addition to the national territories and populations of North America, will European allies be included within the missile defense umbrella? If so, should the entirety of NATO’s membership be included or a subset of that membership, and on what basis should inclusion or exclusion be decided? States not included might resent being slighted. The United States might decide to demand a quid pro quo for Golden Dome protection: such as, for example, a commitment of additional conventional forces to NATO defense or a greater percentage of their gross domestic products to military production and innovation in support of the alliance.

Third, U.S. political leaders and military advisors will have to decide what proportion of future defense budgets will be allocated for modernization of strategic offensive nuclear forces, compared to the amounts designated for Golden Dome or other strategic defenses. Even in a growing American economy, competing budgetary priorities will limit “how much is enough” for national defense. Rising national budget deficits will add pressure for deleting or delaying some military modernizations and other defense expenditures. President Trump’s request for a national defense budget of $1.5 trillion in fiscal 2027 has created some sticker shock even among Republican members of Congress. Depending on which political party has a majority in Congress, support for Golden Dome may hit speed bumps and delays that create technology turbulence and strategic impasses.

Fourth, there is the issue of deterrence, not only of Russia, but also of China, since the latter is determined to join the ranks of nuclear superpowers by 2035.[13] There is a military alliance of sorts between Beijing and Moscow, including joint military exercises, but this bonhomie conceals some important differences in strategic priorities. China thinks about strategy in holistic terms: its comprehensive approach includes, in addition to military matters, political, social, economic, cultural and other dimensions.[14] Therefore, Beijing is also interested in deepening post-Putin ties with Russian economic, cultural and political sectors, beyond military cooperation per se. With regard to the United States, China’s priorities include dominance of the South China Sea and extending China’s military reach throughout the Indo-Pacific theater of operations. In the near term, China is focused on Taiwan and the deterrence of any U.S. attempt to interfere with its plans for reunification. Will Golden Dome also be extended to allies in Asia, including Australia, Japan, and South Korea?

Fifth, will the U.S. determination to proceed with Golden Dome inspire a bow wave of international competition for the military uses of space, and if so, what are the consequences of that situation? One of the sidebars of the Cold War was the more or less de facto agreement on the part of major powers to regard space as a domain for peaceful scientific cooperation. That period of space pacifism is now behind us, and space has already emerged as a domain of military competition and potential future warfare. If space is the new “high ground” for deterrence, it might turn out that nuclear weapons are less important than hitherto because their detonation in space would be counterproductive to the successful conduct of any space-based missions by the U.S. or other parties. Specifically, even conventionally armed space weapons that destroy the brain and central nervous systems of states’ capabilities for reconnaissance, communications, geolocation, cyber security, and intelligence collection, inter alia., could return militaries to their World War II-era dependency on industrial age technology. Further to the point: how well will AI decision aids and advanced robotic systems perform in a digital vacuum?

Sixth, in addition to the importance of strategic nuclear forces, a more immediate concern for nuclear crisis stability and for arms control is presented by the possibility of first use of non-strategic or tactical nuclear weapons (NSNW). President Vladimir Putin and other high-ranking Russian officials have made repeated references to the possibility of nuclear first use against opposed forces in Ukraine and-or NATO. Partly in response to longer-range drone attacks by Ukraine on military and economic assets deep in Russian territory, Russia earlier this year held large-scale drills of its theater nuclear forces, including practice launches of nuclear-capable ballistic and cruise missiles. Earlier, Putin in 2024 also announced a revised nuclear doctrine that included a stipulation that any conventional attack on Russia by one nation that is also supported by a nuclear power would be considered a joint attack by both.[15] In turn, the United States has discussed with its NATO allies the possibility of deploying tactical nuclear weapons to additional alliance member states. Currently the United States deploys B61-12 nuclear gravity bombs to five host countries: Belgium, Germany, Italy, the Netherlands, and Turkiye, in support of NATO’s dual-capable aircraft (DCA) mission. In addition, the UK, while maintaining its own fleet of strategic ballistic missile submarines (SSBNs) and submarine launched ballistic missiles (SLBMs), might also have quietly rejoined the DCA program. Among other states that might be interested in hosting American tactical nuclear weapons, Poland and the Baltic states are serious candidates. And Finland’s parliament voted June 17, 2026 to lift its ban on nuclear weapons, allowing that country to receive, transport and facilitate the movement of nuclear weapons on its territory as part of allied operations.[16] Additional NATO nuclear forwardism is adumbrated in recently revised French nuclear doctrine that anticipates greater shared mission planning and readiness training with European allies.[17] All of this signaling and diplomacy supported by non-strategic nuclear weapons raises the visibility of extended deterrence and, perhaps, moves the issue of theater missile defenses, connected to Golden Dome or otherwise, higher on the military and political to-do lists.

Conclusions

Strategic antimissile and air defenses are almost certainly headed for technological improvement and increased significance in the portfolios of nuclear superpowers. The basing of missile defense components in space as well as terrestrially creates challenges in nuclear C3, in warning and attack assessment, and in estimation of missile defense performance under conditions of enemy countermeasures. The United States will be competitive in a new environment that privileges the space and cyber domains as the front ends of deterrence credibility, but success will require perseverance across U.S. government agencies and coordination with NATO allies. Whether nuclear deterrence among three nuclear superpowers will remain grounded primarily in assured retaliation, or become more dependent on a blend of assured retaliation and defense assertiveness, takes scientists and military theorists into terra incognita.