# Missile Defense Agency

The Missile Defense Agency (MDA) is a component of the United States government's Department of Defense responsible for developing a comprehensive defense against ballistic missiles. It had its origins in the Strategic Defense Initiative (SDI) which was established in 1983 by Ronald Reagan and which was headed by Lt. General James Alan Abrahamson. Under the Strategic Defense Initiative's Innovative Sciences and Technology Office headed by physicist and engineer Dr. James Ionson, the investment was predominantly made in basic research at national laboratories, universities, and in industry. These programs have continued to be key sources of funding for top research scientists in the fields of high-energy physics, advanced materials, nuclear research, supercomputing/computation, and many other critical science and engineering disciplines—funding which indirectly supports other research work by top scientists, and which was most politically viable to fund from appropriations for national defense. It was renamed the Ballistic Missile Defense Organization in 1993, and then renamed the Missile Defense Agency in 2002. The current director is Lieutenant General Heath A. Collins.
Rapid changes in the strategic environment due to the rapid dissolution of the Soviet Union led, in 1993, to Bill Clinton focusing on theater ballistic missiles and similar threats, and renaming it the Ballistic Missile Defense Organization, BMDO. With another change to a more global focus made by George W. Bush, in 2002 the organization became the Missile Defense Agency.
The Missile Defense Agency is partially or wholly responsible for the development of several ballistic missile defense (BMD) systems, including the Patriot PAC-3, Aegis BMD, THAAD and the Ground-Based Midcourse Defense system with a cost of $246 billion. They also led the development of numerous other projects, including the Multiple Kill Vehicle and the newer Multi-Object Kill Vehicle, the Kinetic Energy Interceptor and the Airborne Laser. As the inheritor of the SDI and BMDO work, the MDA continues to fund fundamental research in high-energy physics, supercomputing/computation, advanced materials, and many other science and engineering disciplines.

## Mission statement

The MDA currently publishes the following mission statement:
   "The Missile Defense Agency's (MDA) mission is to develop and deploy a layered Missile Defense System to defend the United States, its deployed forces, allies, and friends from missile attacks in all phases of flight."
The National Defense Authorization Act is cited as the original source of the MDA's mission:
   "It is the policy of the United States to maintain and improve an effective, robust layered missile defense system capable of defending the territory of the United States, allies, deployed forces, and capabilities against the developing and increasingly complex ballistic missile threat with funding subject to the annual authorization of appropriations and the annual appropriation of funds for National Missile Defense. National Defense Authorization Act (Public Law 114–328)"

## International mission

Ballistic Missile Defense Systems (BMDS) must be capable of operating in different regions of the world to ensure the success of the MDA mission. The International Strategy was approved by the MDA Director in 2007. The general strategy for international efforts is:
    Outreach: Communicate the importance of missile defense by promoting worldwide BMDS by sharing information with allies and partners.
    Capability and Interoperability: Identify and integrate U.S and partner systems to create global missile defense system. Promote interoperability among allies.
    Technology: Identify and evaluate possible international technology in support of BMDS capabilities.
    Investment: Identify and execute investment opportunities with allies and partners.
    Workforce: Shape a qualified workforce to execute the MDA International Strategy.
As of 2017 MDA was working on facilities in Germany, Romania, Poland, Japan, Qatar, Saudi Arabia and the United Arab Emirates.

## Potential threats against the United States

Ballistic missile systems using advanced liquid- or solid-propellant propulsion are becoming more mobile, accurate and capable of striking targets over longer distances and are proliferating worldwide.$^{:pp.18–19/61}$
* Iran currently has short- and medium- range missiles with guidance systems. Iran's launch of a medium range, solid fuel ballistic missile demonstrates its ability to hit targets in Israel and southern Europe. Iran also successfully launched the Safir Space Launch Vehicle on Feb 2, 2009. It was then speculated that development of an ICBM was not far behind. Intelligence reports that a missile could have been built sometime between 2010 and 2015 perhaps using help from Russian and North Korean technology. Iran also recently developed a hypersonic ballistic missile in 2022, which can move fifteen times the speed of sound and can reach U.S. and European targets, as well as the U.S. mainland, in 15 minutes.
* North Korea currently deploys a Nodong ballistic missile capable of hitting Japan and South Korea, and is developing a new intermediate-range ballistic missile (IRBM) which could reach Guam and the Aleutian Islands. They also successfully demonstrated the staging and separation technologies required to launch a Taepo-Dong 2 ICBM, which has the capability to reach the United States. The Taepodong missile was first tested in 2006, and failed 40 seconds into midflight. North Korean missiles are notoriously unreliable, and many of the DPRK's missile tests have failed, including the most recent Taepodong-2 launches in 2009 and 2012, and a failed launch of the BM25 Musudan in 2016. On 1 January 2017, North Korea announced its final preparation for a test of an ICBM, for the first time. On 6 March 2017, North Korea launched four missiles from Tongchang-ri, a known long-range missile site at 7:36 a.m. local time, one of which landed in the Sea of Japan, with the remaining three missiles landing in Japan's economic zone. On July 4, 2017 North Korea launched a ballistic missile that had the potential to be an ICBM. It flew through space and landed in the Sea of Japan. "The launch continues to demonstrate that North Korea poses a threat to the United States and our allies," a Pentagon statement said.
* Syria has been identified as a host for short-range ballistic missiles (as it acquires equipment from North Korea and Iran).$^{:p.19/61}$

### Defense of Guam

MDA will be using multiple technologies to defend Guam.

## Categories

MDA divides its systems into four phases: boost; ascent; mid-course; and terminal. Each of these corresponds to a different phase of the threat ballistic missile flight regime. Each phase offers different advantages and disadvantages to a missile defense system (see missile defense classified by trajectory phase), and the geography of each defended area dictates the types of systems which can be employed. The resultant flexible and layered defense approach concept is believed to improve overall defense effectiveness. The more opportunities a system has to neutralize a threat (e.g., by shooting down a missile), the better the chance of success.
Activities have also been categorized as fulfilling the goals of one of five "blocks". For example, "block 4.0" was stated as "Defend Allies and Deployed Forces in Europe from Limited Iranian Long-Range Threats and Expand Protection of U.S. Homeland". It included the US missile defense complex in Poland to be constructed, and the European Mid-course Radar (EMR), currently located at the Ronald Reagan Ballistic Missile Defense Test Site at Kwajalein Atoll, which was to have been modified and relocated to the Czech Republic.
On 17 September 2009, the Obama administration scrapped the "block 4.0" plan, in favor of a new so-called "European Phased Adaptive Approach" (EPAA).

### Boost phase

Can intercept all ranges of missiles, but the missile boost phase is only from one to five minutes. It is the best time to track the missile because it is bright and hot. The missile defense interceptors and sensors must be in close proximity to the launch, which is not always possible. This is the most desirable interception phase because it destroys the missile early in flight at its most vulnerable point and the debris will typically fall on the launching nations' territory.

### Ascent phase

This is the phase after powered flight but before the apogee. It is significantly less challenging than boost phase intercepts, less costly, minimizes the potential impact of debris, and reduces the number of interceptors required to defeat a raid of missiles.

### Midcourse phase

This phase begins after the booster burns out and begins coasting in space. This can last as long as 20 minutes. Any debris remaining will burn up as it enters the atmosphere. Ground-based missile defense systems can defend from long-range and intermediate-range ballistic missiles in this phase. Mobile elements can defend against medium and short ranged missiles in midcourse.

### Terminal phase

This phase is the last chance to intercept the warhead. This contains the least-desirable Interception Point (IP) because there is little room for error and the interception will probably occur close to the defended target.

## Defenses
### Boost phase defense

Research and development:
* Kinetic Energy Interceptor (KEI) – In December 2003, MDA awarded a contract to Northrop Grumman for developing and testing. It will have to be launched from a location not too far from the launch site of the target missile (and is therefore less suitable against large countries), it has to be fired very soon after launch of the target, and it has to be very fast itself (6 km/s). In 2009, the Department of Defense and MDA determined the technological issues were excessive and cancelled the program, allocating no funding for it in its later budget submission.
* Boeing YAL-1 Airborne Laser (ABL) – Team ABL proposed and won the contract for this system in 1996. A high-energy laser mounted on a converted 747 airliner was used to intercept a test target in January 2010, and the following month, successfully destroyed two test missiles. While the program has been cancelled due to concerns about its practicality with present technology (while successful the system was still extremely short ranged, likely needing to fly in heavily defended space to make an interception) the YAL-1 served to demonstrate the potential of such a system. The capabilities of being deployed rapidly to any part of the world and of intercepting a large number of missiles would make a future system extremely attractive. However, the entire concept was deemed infeasible and cancelled without successors in December 2011.
* Network Centric Airborne Defense Element (NCADE) – On September 18, 2008 Raytheon announced it had been awarded a $10 million contract to continue research and development of NCADE, a missile defense system based on the AIM-120 AMRAAM.
One can distinguish disabling the warheads and just disabling the boosting capability. The latter has the risk of "shortfall": damage in countries between the launch site and the target location.
See also APS report.

### Ascent phase defense

Research and development:
* Ascent phase intercept (API) – Emerging intercept technologies are being developed and designed to defeat launched missiles in their ascent phase. This phase is after the boost phase and prior to the threat missile's apogee (midcourse). The Ascent phase intercept program is still classified so there is little information on it.

### Midcourse (ballistic) phase defense

In use:
* Ground-Based Midcourse Defense (GMD)
* Aegis Ballistic Missile Defense System (Aegis BMD)
Research and development:
* Multiple Kill Vehicle (MKV, originally Miniature Kill Vehicle): the Department of Defense has canceled the MKV program for the time being.

### Hypersonic glide phase defense

Research and development:
       This section included material from United States Army Futures Command
By 2021, the Missile Defense Agency (MDA) realized that it almost had a countermeasure to hypersonic boost-glide weapons, by using existing data on the adversary hypersonic systems which were gathered from existing US satellite and ground-based sensors. MDA then fed this data into its existing systems models, and concluded that the adversary hypersonic weapon's glide phase offered the best chance for MDA to intercept it. MDA next proffered a request for information (RFI) from the defense community for building interceptors (denoted the GPI —glide phase interceptor) against the glide phase of that hypersonic weapon. GPIs would be guided by Hypersonic and Ballistic Tracking Space Sensors (HBTSS). These GPI interceptors could first be offered to the Navy for Aegis to intercept using the C2BMC, and later to the Army for THAAD to intercept using IBCS. By 2024, a first test of the hypersonic tracking sensors was imminent.

### Terminal phase defense

In use:
* Terminal High Altitude Area Defense (THAAD)
* PATRIOT Advanced Capability-3 (PAC-3)
* Arrow missile, a joint effort between the U.S. and Israel
Research and development:
* Medium Extended Air Defense System (MEADS), co-developmental program of the United States Department of Defense, Germany and Italy.

## List of directors

| No. | Director | Director | Term | Term | Term | Service branch |
| No. | Portrait | Name | Took office | Left office | Duration | Service branch |
| Director, Strategic Defense Initiative Organization |||||||
| 1 | | Abrahamson, James AlanLieutenant General James A. Abrahamson (born 1933) | March 27, 1984 | January 31, 1989 | 4 years, 310 days | U.S. Air Force |
| 2 | | Monahan, George Lennox Jr.Lieutenant General George L. Monahan Jr. (born 1933) | February 1, 1989 | June 30, 1990 | 1 year, 149 days | U.S. Air Force |
| 3 | | Cooper, Henry F.Ambassador Henry F. Cooper (born 1936) | July 10, 1990 | January 20, 1993 | 2 years, 194 days | U.S. Foreign Service |
| Director, Ballistic Missile Defense Organization |||||||
| 4 | | O'Neill, Malcolm RossLieutenant General Malcolm R. O'Neill (born 1940) | November 22, 1993 | August 1, 1996 | 2 years, 253 days | U.S. Army |
| 5 | | Lyles, Lester L.Lieutenant General Lester L. Lyles (born 1946) | August 1, 1996 | May 28, 1999 | 2 years, 300 days | U.S. Air Force |
| 6 | | Kadish, Ronald T.Lieutenant General Ronald T. Kadish (born 1948) | June 14, 1999 | January 2, 2002 | 2 years, 202 days | U.S. Air Force |
| Director, Missile Defense Agency |||||||
| 6 | | Kadish, Ronald T.Lieutenant General Ronald T. Kadish (born 1948) | January 2, 2002 | July 2, 2004 | 2 years, 182 days | U.S. Air Force |
| 7 | | Obering, Henry Anthony IIILieutenant General Henry A. Obering III (born c. 1954) | July 2, 2004 | November 21, 2008 | 4 years, 142 days | U.S. Air Force |
| 8 | | O'Reilly, Patrick J.Lieutenant General Patrick J. O'Reilly (born c. 1959) | November 21, 2008 | November 19, 2012 | 3 years, 364 days | U.S. Army |
| 9 | | Syring, James D.Vice Admiral James D. Syring (born 1963) | November 19, 2012 | June 16, 2017 | 4 years, 209 days | U.S. Navy |
| 10 | | Greaves, Samuel A.Lieutenant General Samuel A. Greaves (born c. 1963) | June 26, 2017 | May 31, 2019 | 1 year, 339 days | U.S. Air Force |
| 11 | | Hill, Jon AnthonyVice Admiral Jon A. Hill (born 1963) | May 31, 2019 | July 31, 2023 | 4 years, 61 days | U.S. Navy |
| - | | Williams, Douglas L.Rear Admiral (lower half) Douglas L. Williams Acting | August 1, 2023 | December 5, 2023 | 126 days | U.S. Navy |
| 12 | | Collins, HeathLieutenant General Heath A. Collins (born c. 1971) | December 5, 2023 | Incumbent | 360 days | U.S. Air Force |