Space-Based Missile Defense

The Union of Concerned Scientists argues that space-based missile defense is an ineffective and dangerous strategy. The document explains that interceptors in orbit aim to destroy ICBMs during the boost phase to avoid decoy warheads, but this requires a massive number of satellites to ensure coverage. For example, covering North Korea would require 300 to 400 interceptors across seven or eight orbits. The National Academies of Science and Engineering estimated an 'austere' system of 600 interceptors would cost approximately $300 billion. Beyond cost, the system is vulnerable to saturation by multiple simultaneous missile launches and to ground-based anti-satellite weapons. Furthermore, the document warns that such a system would escalate tensions with Russia and China, as interceptors could be perceived as threats to vital military and economic satellites in various orbits, potentially triggering an arms race or military conflict.

• Space-based interceptors are designed to target ICBMs during the 'boost phase' shortly after launch, which prevents adversaries from using decoy warheads to confuse the defense.
• Ensuring constant coverage of a specific region requires a large number of interceptors because satellites in low-altitude orbit circle the Earth rather than hovering; covering North Korea would necessitate 300 to 400 interceptors across seven or eight orbits.
• The financial cost of such a system is extreme, with the National Academies of Science and Engineering estimating that an 'austere' system of 600 interceptors would cost taxpayers about $300 billion, which is roughly half of the annual US military budget.
• The system is technically fragile because it can be overwhelmed by multiple simultaneous missile launches and is vulnerable to ground-launched anti-satellite weapons.
• Deploying these interceptors would likely escalate tensions with Russia and China, as the weapons could be used to attack satellites in low-Earth orbit and higher orbits used for GPS and communications.

APA

Union of Concerned Scientists (2018). Space-Based Missile Defense. https://www.ucs.org/resources/space-based-missile-defense-0

Chicago

Union of Concerned Scientists. Space-Based Missile Defense. 2018. https://www.ucs.org/resources/space-based-missile-defense-0.

Wikipedia

{{cite report |author=Union of Concerned Scientists |title=Space-Based Missile Defense |date=30 August 2018 |url=https://www.ucs.org/resources/space-based-missile-defense-0 |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{unionofconcernedscientists2018spacebased, author = {{Union of Concerned Scientists}}, title = {{Space-Based Missile Defense}}, institution = {Union of Concerned Scientists}, year = {2018}, month = aug, url = {https://www.ucs.org/resources/space-based-missile-defense-0}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }