1 - missle launch,
2 - detection of rocket plumes by space-based sensors,
3 - location of target by early warning radars,
4 - better tracking and target discrimination by X-band radar system,
5 - detection, tracking and targeting of missile by interceptor,
6 - interception.

The different coloured cylinders represent the accuracy with which each component of the system can pin-point the exact position of the target missile.

The individual elements of the system are shown below (see also NMD Program Architecture Fact Sheet from BMDO )

It can be seen that the number and types of detection sensors increase as the system evolves from C-1 to C-3.

All 3 systems would use the 5 current US early-warning radars in California, Massachusetts, Alaska, Greenland and Britain.

These radars provide warning of a nuclear attack to permit the launch of US nuclear weapons before the incoming warheads land.

They are not able to track targets accurately enough to guide interceptors and the Upgraded Early Warning (UEW) Radar program will give them this capability.

These modifications would be complete by C-1 deployment. The C-3 system might include a new, sixth early-warning radar in South Korea.

The upgraded early-warning radars will be extremely limited in their ability to discriminate real warheads from decoys or to deal with other types of countermeasures - so the system will deploy new phased-array X-band radars.

The Space-Based Infrared System, low-earth orbit (SBIRS-low) will have approximately 24 satellites, each equipped with several types of sensors designed to detect missiles during their boost phase and then track targets in midcourse accurately enough to guide interceptors. SBIRS-low is also intended to help discriminate the warhead from decoys or other objects and is currently scheduled for deployment in 2006 (although this date will likely slip) and would first be deployed with the C-2 system. (See official SBIRS web-site and Federation of American Scientists pages on SBIRS .)

The EWR software would be rewritten to incorporate the NMD function and allow the acquisition, tracking, and classification of small objects near the horizon.

The UEWRs would be able to search for different types of missiles, distinguish hostile objects such as warheads from other objects, and provide this data to other NMD elements using improved communications systems.

The radiated peak and average power, radar antenna patterns, and operating bands of the UEWRs would remain unchanged from current operations.

These are ground-based, forward deployed multi-function phased array radars (MFAR) which have evolved from the GBR family including the NMD GBR Prototype (GBR-P) and the Theater High Altitude Air Defense (THAAD) radar.

They use high frequency (5.2-8.5 GHz) and advanced radar signal processing technology to improve target resolution and are designed to provide information about the early phases of a ballistic missile’s trajectory and to provide real-time in-flight tracking data to the NMD Battle Management, Command, Control, and Communications (BMC3) element.

They have a 50^o field of view in both azimuth and elevation, and can be rotated to track targets from any direction. The radar beam would consist of a series of electromagnetic pulses and would be able to operate over a 360^o angle to give full coverage.

These radars incorporate multiple wideband waveforms for improved range resolution, target identification, and discrimination. They have an average power of 170 kW and an antenna area of 123 m² which is equivalent to a power-aperture product of about 20 million. However, each radar consists of a "thinned" array of aerials - only 1/5 of the elements (of the total of 81,000 or so) are present. This decreases the gain by a factor of 5 - with more energy going into sidelobes - but it does have a narrower beam and therefore greater tracking accuracy.

They are intended to be tracking and discrimination radars - surveillance is to be carried out by the UEWRs which will locate targets within a single XBR beamwidth - allowing detection and tracking at long ranges (2,000 - 4,000 km) despite limited power-aperture.

Detailed signature analysis for discrimination of decoys requires a higher signal/noise ratio than tracking, and the range at which discrimination is possible would be significantly less than the maximum detection and tracking range.

When fully operational, approximately 30 to 60 personnel would be associated with operating the X-Band Radar (XBR).

The XBR site would include a radar mounted on its pedestal and associated control and maintenance facility, a power generation facility, and a 150 meter (500-foot) controlled area.

These requirements would encompass an area of approximately 7 hectares (17.46 acres) for the radar only.

Other support infrastructure would probably also be required.

(See also X band Radar Fact Sheet from BMDO )

Both Russia and China are strongly opposed to the implementation of a US Star Wars system (see various articles in the Latest News section). They, along with many other countries, believe it will lead to a new arms race in space.

A major problem seems to be that the system can be seen as offensive as well rather than defensive - it increases the ability of the US to carry out its first strike policy. This concern is hampering progress on further negotiations on SALTIII, the NPT etc.

Another major problem is that it will trigger a response from nations who possess nuclear weapons (to try and swamp the defence system) and generate a new arms race in space.

The US has long sought an unanswerable first strike capability. Two technological advances created the possibility of a very efficient Counterforce strike:

• the miniaturization of warheads
• an enormous increase in warhead accuracy

(“First Strike! The Pentagon’s Plans for Nuclear War”, by R.C.Aldridge 1983, p.97)

President Carter’s Presidential Directives 24 August 1977 - July 1980 clearly defined a first strike strategy with four components:

1. Anti Satellite (ASAT): weapons launched to knock out the Soviet warning system.
2. Decapitation: Destruction of Soviet leadership by very accurate Pershing IIs.
3. Counterforce: Destruction of most of the Soviet missiles in hardened silos, submarines, mobile launchers and the strategic bomber fleet by MX & Trident II (D-5) missiles.
4. Strategic Defence Initiative (SDI) or 'Star Wars: A ballistic missile defence system to mop up any Soviet missiles that survived Counterforce and had been launched.

(“To Win a Nuclear War, The Pentagon’s Secret War Plans” by M. Kaku and D. Axelrod, 1987, p.195)

The importance of a Star Wars shield in a First Strike capability was admitted by Lt. Col. Robert Bowman, U.S. Air Force director, who called it:

(Kaku and Aelrod, 1987, p.242)

The United State's European allies are opposed to BMD (and therefore NMD). They feel that its implementation could raise security issues and lead to a new arms race. Joschka Fisher, the German Foreign Minister, said that the proposed missile shield would lead to "split security standards within the Nato alliance."

French Defense Minister Alain Richard has said:

Foreign Ministry spokeswoman Anne Gazeau-Secret has said that the ABM developments have already blocked the work of the Conference on Disarmament in Geneva. France believes that

French President Jacques Chirac said:

In an interview for the New York Times on 17 December 1999, French President Jacques Chirac also commented:

(See also Statements by Foreign Leaders Opposing NMD
and China, Russia Unify Against U.S. Missile Shield )

SCIENTIFIC PANEL SAYS NMD WON'T WORK
(points taken from the Union of Concerned Scientists' Website - 12/4/00)

• The National Missile Defense system under development by the United States would be ineffective against even limited ballistic missile attacks from emerging missile.
• Its deployment would increase nuclear dangers from Russia and China, and impede cooperation by these countries in international efforts to control the proliferation of long-range ballistic missiles and weapons of mass destruction.
• The United States should reconsider its options for countering the threats posed by long-range ballistic missiles and shelve the current NMD plans as unworkable and counterproductive.
• Our analysis of the effectiveness of the NMD system assumes it has all of the sensors and interceptors planned for the full system to be deployed only by 2010 or later. However, countermeasures could be deployed more rapidly and would be available to potential attackers before the United States could deploy even the much less capable first phase of the system.
• The contributors to the study are all physicists or engineers. Our analysis is based on an understanding of basic physics and technology and uses only information available in the open literature.
• The United States must assume that any potential attacker would conduct a similar, although far more sophisticated, analysis.

• The planned NMD system could be defeated by technically simple countermeasures. Such countermeasures would be available to any emerging missile state that deploys a long-range ballistic missile.
• Many operational and technical factors make the job of the defense more difficult than that of the attacker.
• The planned NMD system would not be effective against an accidental or unauthorized attack from Russia, or an erroneous launch based on false warning of a US attack.
• The planned NMD system would not be effective against a Chinese attack.
• Long-range missiles would be neither the only nor the optimum means of delivery for an emerging missile state attacking the United States with nuclear, biological, or chemical weapons.
• Available evidence strongly suggests that the Pentagon has greatly underestimated the ability and motivation of emerging missile states to deploy effective countermeasures.
• The planned testing program for the NMD system is inadequate to assess the operational effectiveness of the system.
• Past US missile defense tests against missiles using "countermeasures" did not demonstrate that defenses could defeat such countermeasures.
• NMD deployment would result in large security costs to the United States.
• Deterrence will continue to be the ultimate line of defense against attacks on the United States by missiles armed with weapons of mass destruction.

(From Countermeasures - the full report on NMD from The Union of Concerned Scientists)

The Clinton administration has stated that it will use the following criteria when making its deployment decision:

1. the changing threat from emerging missile states and the anticipated need for an NMD system
2. the cost of deployment
3. the effect of NMD deployment on US-Russian nuclear arms reduction process and the broader strategic environment
4. the "technological readiness" of the system for deployment

Some NMD proponents acknowledge that neither these intercept tests nor the upcoming deployment readiness review will assess the operational effectiveness of the planned system against countermeasures. However, they argue that if these intercept tests demonstrate that the basic technology works, the United States should deploy the first stage of the system and then upgrade it so that the fully deployed NMD system would be able to deal with countermeasures.

However, since the real-world threat would include countermeasures, then the criterion for deployment must be whether the fully deployed system would be able to deal with these countermeasures-not the much more narrow criterion of whether the system can intercept cooperative targets on the test range.