Missile Defense in the 21st Century: Technical Efficacy and Deterrence

By Eric Auner

Topics Addressed – How do analysts and policymakers in the United States and elsewhere assess whether U.S. missile defense “works” on a technical level, given that current U.S. systems (besides Patriot) have not been used in combat? – How do assessments of technical efficacy relate to the ability of U.S. systems to meet U.S. deterrence goals?

Outline of Current U.S. BMD Systems and Activities • Regional arrangements: – The European Phased Adaptive Approach (EPAA). • The deployment of gradually more capable BMD assets to Europe through 2020.

– Planned regional system in the Persian Gulf. – Planned regional system in the Asia Pacific.

• Homeland defense: – Ground-based Midcourse Defense. – Phase IV of the EPAA (increasingly in doubt?).

• • • • •

Other land-based systems (THAAD, PAC-3). Sea-based systems (Aegis, SM-3). Other cooperative efforts and exercises (Israel, Japan, etc.). Space-, land-, and sea-based sensors. Command and control/networking.

Current Purposes of U.S. BMD in the 21st Century (Across Parties and Administrations): • •

• •

Defend homeland and certain allies against limited strikes from outlier states. – Current systems not designed to counter large raid sizes. Provide a technological/policy/joint threat assessment forum for engaging and reassuring current, emerging, and potential partners. – Current partners: (NATO, Israel, Japan) – Emerging partners: (GCC, India?) – Potential partners: (Russia? China?) Hedge against the evolution and expansion of ballistic missile threats. Deter the acquisition and use of ballistic missiles : – President George W. Bush (2001): “Deterrence can no longer be based solely on the threat of nuclear retaliation. Defenses can strengthen deterrence by reducing the incentive for proliferation.” – Obama Administration Ballistic Missile Defense Review (2010): “The United States seeks to create an environment in which the development, acquisition, deployment, and use of ballistic missiles by regional adversaries can be deterred, principally by eliminating their confidence in the effectiveness of such attacks.”

Publicly Available Assessments of Technical Efficacy • Military assessments and statements. • Public information about testing: – Creates ambiguous record open to different interpretations.

• Public information about simulations and exercises. • Government commissions and other analyses. • Non-governmental expert analyses.

Objects of Technical Assessment • Interceptors: – Booster – Kill vehicle – Exo-atmospheric discrimination (decoys, missile debris, etc.)

• Sensors: – Detecting launches – Tracking missiles – Kill assessment

• Networking: – Incorporating and interpreting multiple data streams within a very short time window. – Complexity and challenge compounded if partner assets/data integrated into U.S. firing decisions/interception attempts.

• Command and control

How is the Technical Efficacy of U.S. Systems Conveyed to Other States? • Media reports • Public U.S. government statements – Jay Carney (3/7/2013): “I can tell you that the United States is fully capable of defending against any North Korean ballistic missile attack. And our recent success in returning to testing of the upgraded version of the so-called GBI, or the CE-2 missile, will keep us on a good trajectory to improve our defense capability against limited ballistic missile threats such as those from North Korea. But let’s be clear, we are fully capable of dealing with that threat.”

• U.S. government statements made behind closed doors • Publicly available unclassified studies • Governmental and non-governmental analyses carried out in other countries

Potential Contributions of BMD to Deterrence • BMD deployments may convince a potential aggressor that: – a missile strike will be unsuccessful. – a successful missile attack would require such a large raid size that massive retaliation would be assured. In other words, pin-prick attacks would be deterred by BMD, massive attacks would be deterred by conventional and nuclear forces. – missile attacks will not cause the intended level of damage (if some, but not all, warheads are intercepted). – defenses will preserve the means of retaliation. – BMD commitments to partner nations represent broader security commitments.

What Level of Technical Efficacy Is Necessary to Meet U.S. Deterrence Goals? • Must systems be seen by potential attackers to work 100% of the time in operationally-realistic conditions? – Would a 75% overall anticipated probability of interception be sufficient? – Would 50% or 25% be sufficient? – Might even a low probability of intercept cause an attacker to choose a different, undefended target?

• Do allies and partners believe that their enemies see U.S. BMD systems as effective? • How do potential aggressors assess whether U.S systems are effective?

Final Takeaways and Questions for Further Inquiry • The perceived technical efficacy of BMD systems should be analyzed alongside the actual technical efficacy of those systems. – This would obviously change if those systems were actually forced to engage an incoming ballistic missile in combat, creating an operational success record.

• Which sources of information do adversaries rely on/trust to evaluate U.S. BMD systems? • How, if at all, are foreign perceptions affected by the internal U.S. debate? • If the United States become less confident in its own systems, do potential assailants become more confident in their ability to defeat those systems? • Does the perceived efficacy of U.S. BMD systems affect the propensity of adversaries to make missile threats? Does the perceived efficacy of these systems affect U.S. responses to such threats? Allied/partner responses?