Defense Primer: Ballistic Missile Defense

Updated October 9, 2019 Defense Primer: Ballistic Missile Defense The United States has been developing and deploying ballistic missile defenses (BMD) to defend against enemy missiles continuously since the late 1940s. In the late 1960s and early 1970s, the United States deployed a limited nuclear-tipped BMD system to protect a portion of its U.S. land-based nuclear ICBM (intercontinental ballistic missile) force in order to preserve a strategic deterrent against a Soviet nuclear attack on the Homeland. That system became active in 1975 but shut down in 1976 because of concerns over cost and effectiveness. In the FY1975 budget, the Army began funding research into hit-to-kill or kinetic energy interceptors as an alternative—the type of interceptor technology dominates U.S. BMD systems today. In 1983, President Reagan announced an enhanced effort for BMD. Since the start of the Reagan initiative in 1985, BMD has been a key national security interest in Congress. It has appropriated well over $200 billion for a broad range of research and development programs and deployment of BMD systems here and abroad. North Korea likely has an arsenal of hundreds of SRBMs that can reach all of South Korea and perhaps dozens of MRBMs (whose reliability at this point remains uncertain), capable of reaching Japan and U.S. bases in the region. North Korea is in the process of developing an ICBM capability that could strike the U.S. homeland with a nuclear warhead. Although North Korea has conducted a number of nuclear tests, it is unclear whether any of their ballistic missiles are armed with a nuclear warhead. The IC assesses that Iran has the largest inventory of ballistic missiles in the Middle East. Those missiles are armed with conventional warheads; Iran does not have a nuclear weapons capability. Most of Iran’s ballistic missile force consists of SRBMs with ranges less than 500 km, which it views as a tactical warfighting force. Iran also has a growing and significant number of MRBMs capable of striking targets throughout the region, which it views as a deterrent force. Iran does not appear to have a dedicated ICBM program. The Missile Defense Agency (MDA) is charged with the mission to develop, test, and field an integrated, layered, BMD system (BMDS) to defend the United States, its deployed forces, allies, and friends against all ranges of enemy hypersonic and ballistic missiles in all phases of flight. Current U.S. policy, however, is not directed at the strategic nuclear deterrent forces of Russia and China. The FY2020 budget request is $13.6 billion for missile defense, $9.4 billion of which is for MDA. Almost all of China’s SRBMs are deployed at bases opposite Taiwan. China’s MRBMs can reach U.S. bases, as well as U.S. friends and allies in the region. China’s missile forces could also target U.S. naval ships in Northeast Asia. Additionally, China is working on a range of technologies to attempt to counter U.S. and other countries’ BMD systems. China’s ICBM and some nuclear-armed MRBM forces are intended for strategic and regional deterrence. Ballistic Missile Threats The United States has deployed a global array of networked ground, sea, and space-based sensors for target detection and tracking, an extensive number of ground- and sea-based hit-to-kill (direct impact) and blast fragmentation warhead interceptors, and a global network of command, control, and battle management capabilities to link those sensors with those interceptors. After an initial powered phase of flight, a ballistic missile leaves the atmosphere and follows an unpowered trajectory or flight path before reentering the atmosphere toward a predetermined target. Ballistic missiles have an effective range from a few hundred kilometers to more than 10,000 kilometers (km). Short-range ballistic missiles (SRBMs) range from 300-1,000 km and are generally considered for tactical military use. Medium-range ballistic missiles (MRBMs) have a range from 1,000-5,500 km, although most are armed with conventional warheads and range less than 3,500 km. ICBMs range further than 5,500 km and are generally considered as strategic deterrent forces. Most of the world’s ballistic missiles belong to the United States and its friends and allies. Russia, especially, and China have significant numbers of ICBMs. Russia continues to possess intermediate-range ballistic cruise missiles (3,500-5,500 km), which led to the U.S. withdrawal from the 1987 INF (Intermediate Nuclear Forces) Treaty. The ballistic missile threats of most concern to the United States today are primarily the SRBM and MRBM forces from North Korea, Iran and China, and growing North Korean ICBM capabilities. The Major Elements of the U.S. BMDS Ground-based Midcourse Defense (GMD) Since 2004, the United States has deployed a force of 44 (expanding now to 64) Ground-based Interceptors (GBI) at Ft, Greely, Alaska and Vandenberg Air Force Base, California. The GMD system is designed to destroy a limited attack in space from ICBMs aimed at the United States, to include from North Korea and even Iran. Although the GMD system is praised by senior military leaders and is generally viewed in successful terms, it does have a somewhat mixed flight test record. Terminal High Altitude Area Defense (THAAD) THAAD is a highly mobile, rapidly deployable BMD system designed to shoot down attacking short- and medium-range missiles during their final or terminal phase of flight. It is designed to provide broad area coverage Defense Primer: Ballistic Missile Defense against threats to population centers and industrial resources as well as military forces. THAAD was initially proposed in 1987 and its first flight test occurred in April 1995. It had a very poor test record until the first successful intercept in 1999. In recent years, THAAD’s test record has demonstrated high effectiveness and reliability. Many now consider it the most advanced BMD system in the world. The United States has delivered seven THAAD batteries to the U.S. Army. U.S. THAAD batteries are now deployed in Guam, South Korea, and the Persian Gulf. THAAD radars are exceptionally powerful and are currently deployed in Turkey, Israel, and Japan. Any future THAAD batteries produced will be for Foreign Military Sales. Aegis BMD The Aegis BMD program gives Navy Aegis cruisers and destroyers a capability for providing regional defense against short- and medium-range ballistic missile attacks. Under the FY2020 budget submission, the number of BMD-capable Navy Aegis ships is projected to increase from 38 to 59 at the end of FY2024. Aegis BMD ships and Aegis Ashore (land-based) capabilities in Romania (and Poland by 2020) contribute to NATO’s territorial defense mission. Testing results have shown significant Aegis BMD capabilities. Patriot Advanced Capability-3 (PAC-3) The Army Patriot system is the most mature element of the BMDS. It was used in combat in the 1991 and 2003 Iraq wars and is fielded around the world by the United States and many others that have purchased the system. Patriot is a mobile, transportable system designed to defend areas such as military bases and air fields. Patriot works with THAAD to provide an integrated and overlapping defense against attacking missiles in their final phase of flight. Foreign BMD Participation Other Regional BMD Cooperative Efforts Similar to the EPAA, the United States has sought since 2010 to formalize a regional cooperative BMD capability both in Northeast Asia (with Japan, Korea and Australia) and in the Persian Gulf. Although many of the BMD elements of a potential cooperative system are in place in these regions, wariness between likely foreign partners and opposition from countries such as China have prevented a formal agreement and participation from going forward. Cooperation with Israel Since 1986, the United States has invested significantly in Israel’s missile defense programs and systems designed to protect against missile and rocket attacks. The United States also provided a THAAD radar to Israel in 2008.Thus far, the United States has provided about $2.5 billion for Israeli programs, which include the Arrow systems designed to counter short- and medium-range ballistic missiles, Iron Dome (to counter short-range rockets), and David’s Sling (designed to counter longer range rockets). Legislative Issues BMD has broad support across the political spectrum and within the military as evidenced by the high degree of funding support for the program regardless of which party controls the White House and Congress, especially since the early 2000s. Where Congress has cut programs tends to fall in three areas: where program delays allow for opportunistic program cuts, cuts for long-lead procurement of components with still questionable test results, and newer programs not likely to come to fruition in the short or medium term. Congress has also thus far been unwilling to fund programs that might lead to emplacing interceptor capabilities in space. But this reticence may now be changing as the geopolitical and space domain is changing. Relevant Statutes The United States has missile defense cooperative programs with multiple allies. MDA actively participates in NATO activities to develop an integrated NATO BMD capability. Patriot systems have been purchased by allies, acquisition of THAAD is in various stages of contract negotiation and acquisition, and countries such as Japan have acquired Aegis BMD capabilities. The Kingdom of Saudi Arabia (KSA) is on contract to receive seven THAAD batteries. European Phased Adaptive Approach (EPAA) At the 2010 Lisbon Summit, NATO agreed to develop a missile defense capability to protect NATO European populations, territory and forces against the threats posed by the proliferation of ballistic missiles. The U.S. contribution to that NATO effort is the EPAA, which includes the deployment of a THAAD radar in Turkey, the deployment of Aegis BMD ships in Europe, and the deployment of an Aegis Ashore in Romania. A second Aegis Ashore capability is being constructed in Poland, which will complete the U.S. commitment to NATO’s territorial defense. P.L. 106-38 – National Missile Defense Act of 1999. CRS Products CRS In Focus IF10472, North Korea’s Nuclear and Ballistic Missile Programs, by Steven A. Hildreth and Mary Beth D. Nikitin CRS Report R42849, Iran’s Ballistic Missile and Space Launch Programs, by Steven A. Hildreth CRS Report RL33745, Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress, by Ronald O'Rourke CRS Report R43116, Ballistic Missile Defense in the Asia-Pacific Region: Cooperation and Opposition, by Ian E. Rinehart, Steven A. Hildreth, and Susan V. Lawrence Other Resources DOD. 2019 Missile Defense Review. Jan. 2019. Stephen M. McCall, Analyst in Military Space, Missile Defense, and Defense Innovation IF10541 Defense Primer: Ballistic Missile Defense Disclaimer This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of information that has been provided by CRS to Members of Congress in connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or material from a third party, you may need to obtain the permission of the copyright holder if you wish to copy or otherwise use copyrighted material. | IF10541 · VERSION 6 · UPDATED