Golden Dome and a New Kind of Nuclear Arms Race

Nuclear arms control is comatose. The United States and Russia allowed New START to expire in February, ending the last vestige of formal restraint on deployed nuclear arsenals. While there is some appetite to resuscitate the process, President Trump has cited the People’s Republic of China’s (PRC) absence as a justification for accepting the expiration and pursuing a new trilateral deal. Beijing maintains that it is uninterested in arms limitation talks until the U.S. and Russia reduce their stockpiles. With PRC buildup occurring, the United States no longer constrained by treaty, and the White House pushing for new nuclear initiatives in the Golden Dome, both sides appear primed for an arms race.

Unlike the arms race of the Cold War, this one cannot be adequately measured by warhead counts. It will consist of integrated architectures of space-based interceptors, counterspace weapons, hypersonic delivery vehicles, and command and control networks that bind them all together. The value of each system relative to an adversary’s could be harder to quantify, agreements harder to reach, and miscalculations easier to stumble into. Analyses from various sources project extraordinary costs and significant limitations for Golden Dome. Congress should carefully consider whether the funding of this program is worth the risk of inflaming an arms competition that neither side yet fully understands.

Background

The PRC continues to expand and reorganize its military, with a 7% spending increase slated for 2026. While many analysts consider official figures untrustworthy, the stated increase aligns with independent estimates. The PRC has directed a considerable portion of this spending towards its nuclear arsenal, expanding its warhead count and pursuing advancements in delivery capabilities. The main question is how far this buildup will go. Beijing remains officially committed to a policy of minimum deterrence and non-engagement in arms racing, but may continue towards 1,500 and approach the size of the U.S. deployed arsenal. 

Golden Dome was introduced in a January 2025 executive order and received top billing in the White House’s requested $1.5 trillion defense budget. This budget represents a more than 40% increase and expands ongoing nuclear modernization efforts. The program’s eventual scope and cost remain deeply uncertain. The director of the program, Michael Guetlein, estimates $185 billion, while independent assessments are often far higher. The American Enterprise Institute has developed a range of potential packages, from $252 billion to $3.6 trillion, depending on capability choices. The most expensive package estimates are the ones reliant on space-based interceptors (SBIs) for their functionality. The Congressional Budget Office (CBO) estimates roughly $1.2 trillion over twenty years (more than six times the administration’s estimate). The CBO has attributed the bulk of this cost to a proposed constellation of 7,800 SBIs, which account for about 70% of acquisition costs. Director Guetlein has contested the CBO figure, arguing “they’re not estimating what we’re building.” With SBI contracts already awarded, tests underway, and $23 billion committed, the United States is accelerating development before resolving what it is developing. Full funding may face headwinds in Congress, but even a fraction of the proposed increase represents a substantial commitment to a space-based missile defense whose scope and effectiveness are in question. Yet, while the system appears unlikely to ever reliably intercept large-scale ICBM salvos, it would still be a nuisance to the PRC.

A New Arms Race

Arms races do not arise only from hostility or lack of agreements. They tend to occur when one side faces a force asymmetry and has the will and ability to rectify it. A nuclear asymmetry that threatens the secure second-strike capability of a country is so crucial that it demands a buildup. Unlike during the Cold War, the ability to assure destruction in the case of conflict is now far less reliant on the sheer volume of weapons. It is reliant on the ability of delivery, monitoring, and communications systems to avoid preemptive destruction in the case of conflict and to reliably function. This added complexity could make future arms-control agreements more difficult.  

Golden Dome will likely fall short of its ambitions, but Beijing’s safest course may be to plan for somewhere between a bad and a worst-case scenario. Development timelines are measured in years, and once policymakers decide to proceed, it can be politically and practically difficult to stop. Further, if Golden Dome does not work as intended and Beijing builds past it, then the United States would face a choice between spending more on other measures, accepting the new reality, or trying to negotiate away parts of the threat. Accepting a PRC with a more aggressive nuclear posture, perhaps comparable with the United States or Russia, is undesirable. Beijing has rejected negotiations so far. Unlike the Soviet Union for its last two decades of existence, the PRC does not currently face severe economic pressures from past military overspending nor a stagnant economy. Beijing may even functionally outspend Washington, given its current industrial capacity and advantages in domestic purchasing power.

Threats to the PRC

Nuclear and conventional deterrence today rely on an intensely integrated network of observation and communication systems. Golden Dome intends to intercept missiles during the boost phase, immediately after launch and before exiting the atmosphere, requiring a round-the-clock ability to detect, fire, and strike missiles within a five-minute window. AEI estimates that 1,900 SBIs, alongside the required supporting systems, would be necessary to cover each point on Earth with an average of two interceptors at any time. While any exact endpoint in terms of systems amounts to speculation at this point in the program’s development, the estimated initial procurement cost of USD 17 billion and replacement cycles of five years for this option mean it could be an achievable goal that aligns well with the executive orders’ intentions.

Even at modest levels of development, Golden Dome poses a real challenge to PRC strategic planning. The ability to strike targets within minutes could inspire serious fear, as depending on interceptor designs, the distinction between an offensive and defensive posture could be blurry. Further, if the eventual SBI platform designs allow for them to be aimed not only at the Earth but at other satellites, then Golden Dome will force the PRC to take countermeasures to defend its space-based assets. Golden Dome, even at modest levels of spending, could plausibly obtain the capability to intercept limited numbers of missiles, strike anywhere on the planet in minutes, and threaten adversary space assets. In the event of conflict, Golden Dome could significantly change the battlespace regardless of whether it ends up being an evolution or revolution in the current U.S. defense posture. 

Even though Golden Dome will likely be incapable of blocking large-scale missile salvos, if it can plausibly block a significant number, it might sway the PRC to continue its nuclear buildup beyond current plans. If Beijing intends only to maintain its minimum deterrent, the U.S.’ ability to intercept even a small portion of that force could induce expansion beyond current intentions. Worst-case scenarios for PRC warhead count may then become a self-fulfilling prophecy. 

The cost of shooting down a missile will remain higher than the cost of building one, especially given the difference in purchasing power between the U.S. and the PRC. At a minimum, Beijing is likely to double down on areas of perceived advantage, such as hypersonic or fractional orbital bombardment delivery systems that are capable of penetrating missile defenses. Expanding the already dominant U.S. position in space-based capabilities will also require the PRC to continue developing counterspace capabilities. This cost asymmetry ensures that any U.S. attempt to neutralize the PRC deterrent will drive Beijing to expand and diversify rather than capitulate. 

Beijing’s diplomatic reaction to the Golden Dome has been negative, arguing that it undermines strategic stability and worsens international tensions. Even at a limited capability level, Golden Dome represents a clear departure from Washington’s past justifications for missile defense after leaving the Anti-Ballistic Missile Treaty. Missile defense is no longer exclusively for preventing strikes from rogue states or terrorist groups that cannot be deterred with nuclear retaliation. The emphasis on SBIs from the outset has clearly differentiated Golden Dome from the more limited Ground-Based Midcourse Defense (GMD) and invites comparisons to the Reagan administration’s Strategic Defense Initiative, widely viewed at the time as destabilizing. 

Golden Dome, especially if it receives high levels of funding, signals a more aggressive nuclear posture by the United States. It is, by executive order, an attempt to escape from the condition of mutually assured destruction. It runs completely counter to the PRC’s stance on no-first-use, which requires some level of mutually recognized vulnerability for stability. Even if Beijing is skeptical of the proposed defensive shield ever functioning, the U.S.’ willingness to invest large amounts of money in it might empower more hawkish members of the Chinese Communist Party to justify similar pursuits or countermeasures. Chinese officials can now more easily frame the United States as a potential nuclear aggressor, and this will create arms-racing pressure as more hawkish factions marginalize dovish voices. Golden Dome may widen gaps in what each side views as stabilizing and complicate future negotiations.  

Conclusion

A new nuclear arms race is not inevitable. If it does occur, it will not look the same as that against the USSR. This race may not be measurable in warheads but instead consists of an array of systems. This complexity will make it more difficult to understand and agree on what stability or security means, create additional difficulties and expenses for both sides, and likely involve novel risks. It will happen in a multipolar world that adheres less to international laws and norms with each passing day. Golden Dome, in combination with increased U.S. military spending and a perceptibly more aggressive posture, will put pressure on the PRC to begin or accelerate arms racing.

Congress should deeply consider during upcoming budgetary debates whether it wishes to risk going down this road, given that its own budget office has estimated the Golden Dome’s extraordinary cost and limited effectiveness. If Congress is willing to, then it should do so with open eyes as to the potential for initiating a long chain of reactions that could be difficult to stop, and where the United States is not guaranteed to come out ahead. Investments in space-based systems and nuclear modernization are not all equally escalatory, and policymakers should consider alternative ways forward that revitalize and reform the U.S. defense industrial base. 

Views expressed are the author’s own and do not represent the views of GSSR, Georgetown University, or any other entity. Image Credit: South China Morning Post