Ballistic Missile Defense Terminal Defense Segment

The Ballistic Missile Defense Terminal Defense Segment (PE 0603881C), managed by the Missile Defense Agency (MDA), is a critical component of the Department of Defense's efforts to provide forward-deployable, regional missile defense capabilities. The overarching goal of this program element is to research, develop, test, and evaluate advanced terminal phase missile defense systems that can intercept and destroy short-, medium-, and limited intermediate-range missile threats, including emerging hypersonic and maneuvering threats, during their terminal phase of flight. The FY 2026 budget request reflects investment in both discretionary and mandatory funds to accelerate the delivery of next-generation missile defense capabilities and to integrate these systems into the Army's Integrated Air and Missile Defense (IAMD) Battle Command System (IBCS) architecture.

MD07: Terminal High Altitude Area Defense (THAAD) is the primary line item within this program element, with FY 2026 funding supporting iterative development and integration of multiple, independent system builds. The main objectives for THAAD include enhancing system reliability, availability, and readiness, as well as expanding engagement capabilities against advanced threats such as hypersonic and non-ballistic missiles. The program is adopting agile, industry-proven development methodologies to enable rapid delivery of new capabilities, including advanced threat algorithms, improved communications, enhanced radar discrimination, and cyber security upgrades. A key focus is the integration of THAAD into the Army's IBCS, enabling a more unified and flexible missile defense architecture. The budget also supports modernization of development labs and incorporation of lessons learned from real-world events to improve system performance and sustainment.

MC07: Cyber Operations supports the cybersecurity posture of the THAAD system and associated mission systems. The objectives of this line item are to sustain the MDA's Risk Management Framework (RMF) and Controls Validation Testing (CVT) activities, conduct risk assessments, and ensure compliance with the Federal Information Security Management Act. Funding is used for cybersecurity engineering, architecture planning, vulnerability assessments, and the development of mitigation plans to address information assurance deficiencies. These activities are essential for maintaining the authorization to operate THAAD systems within the broader Missile Defense System and for defending against cyber threats that could compromise mission effectiveness.

MD06: Patriot Advanced Capability-3 (PAC-3) is a legacy line item that previously supported the integration of the Army's PAC-3 system with the Missile Defense System. While no new funding is requested for FY 2026, past objectives included enabling interoperability between PAC-3 and THAAD, particularly through joint operational needs such as remote launch capabilities and integration of PAC-3 Missile Segment Enhancement (MSE) with THAAD. The Army is now primarily responsible for PAC-3 production and development, with MDA retaining responsibility for integration efforts as needed.

MD40: Program-Wide Support provides non-headquarters management and support costs across all MDA functions and activities related to the Missile Defense System. This includes funding for government civilian personnel, contract support services, deployment site preparation, facility operations, security, audit readiness, STEM programs, and compliance with statutory requirements. The objective is to ensure the integrity, oversight, and operational readiness of the entire missile defense enterprise, supporting both current and future technology development and global deployments.

Across these line items, the Ballistic Missile Defense Terminal Defense Segment is structured to address rapidly evolving missile threats from both rogue states and peer adversaries. The program's objectives are aligned with recent national defense policy directives, including the 2025 Executive Order prioritizing the protection of U.S. citizens, critical infrastructure, and strategic deterrence. The MDA's approach emphasizes speed, flexibility, and integration, leveraging both traditional and non-traditional acquisition strategies to deliver operationally relevant capabilities to the warfighter.