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United States Senate: Letter to Secretary Mattis on Space-Based Missile Defense

Core Content

This letter from Senator Ted Cruz to Secretary of Defense James Mattis addresses the 2018 Missile Defense Review (MDR) and advocates for the development and deployment of a space-based missile defense layer (SBI) as part of the United States' layered missile defense strategy. The letter emphasizes the need for a comprehensive and modernized missile defense architecture to counter emerging threats.

Main Views

• Current Capabilities: The U.S. has made significant progress in missile defense, particularly in midcourse and terminal phase interception using ground- and sea-based systems. This is a proud achievement and a source of national security.
• Vulnerability in Boost Phase: Despite these capabilities, the U.S. lacks a system to intercept ballistic missiles during their most vulnerable stage — the boost phase. This is when the missile is slowest, has the clearest heat signature, and is least able to deploy countermeasures.
• Support for Boost Phase Interception: Senator Cruz commends President Trump's FY2019 budget for its focus on unmanned aerial vehicles (UAVs) and directed energy for boost phase interception. However, he argues that these efforts are not sufficient to ensure credible deterrence in the 21st century.
• Case for Space-Based Interceptor (SBI): A space-based intercept layer is proposed as a necessary addition to the existing defense systems. It would offer real-time monitoring, global coverage, and early engagement of ascending threats, providing more time and opportunities for interception.
• Strategic Importance: The letter highlights the increasing threat from North Korea and Iran, particularly their nuclear ambitions, as well as the development of anti-access/area denial (A2/AD) capabilities in the Persian Gulf and South China Sea. It also notes the great power competition in space, with China and Russia investing in antisatellite weapons and hypersonic glide vehicles that can evade current missile defense systems.
• Policy Alignment: Senator Cruz references his language in the FY2018 National Defense Authorization Act (NDAA), which established a U.S. policy to use an integrated system of space-based assets for homeland defense. He urges the MDR to operationalize this policy by including SBI as a recommended capability.
• Statutory Requirement: The deployment of SBI is statutorily contingent upon recommendations from the Missile Defense Review. Therefore, he requests that the 2018 MDR include SBI as a priority.

Key Information

• Date: February 22, 2018
• Recipient: James Mattis, Secretary of Defense
• Sender: Ted Cruz, United States Senator
• CC: John Rood, Under Secretary of Defense for Policy
• Lt. Gen. Samuel A. Greaves, Director of Missile Defense Agency
• Supporting Documents:
  • 2011 Institute for Defense Analysis (IDA) study: Demonstrated the potential of SBI to defend against ICBMs, antisatellite weapons, and anti-ship ballistic missiles.
  • 2018 National Defense Strategy (NDS): Emphasized the need for modernization and the development of disruptive capabilities for theater and ballistic missile threats.
  • 2018 Nuclear Posture Review (NPR): Highlighted the increasing competition and congestion in space and the need for resilient capabilities to counter threats from China and Russia.

Conclusion

Senator Ted Cruz argues that the U.S. must urgently pursue a space-based missile defense layer to enhance national security and reinforce deterrence in the face of evolving threats. He calls for the 2018 Missile Defense Review to include SBI as a strategic recommendation, aligning with the broader National Defense Strategy and Nuclear Posture Review objectives. The letter underscores the critical role of space in modern defense systems and the need for a proactive approach to ensure the U.S. maintains its technological and strategic edge.