Missile Defense: The Current Debate
Released: 2005-12-21T00:00:00

Summary:
The United States has pursued missile defenses since the dawn of the missile age shortly afterWorld War II. The development and deployment of missile defenses has not only been elusive, buthas been one of the most divisive issues of the past generation until recent years.
The Bush Administration substantially altered the debate over missile defenses. TheAdministration requested significant funding increases for missile defense programs, eliminated thedistinction between national and theater missile defense, restructured the missile defense programto focus more directly on developing deployment options for a "layered" capability to interceptmissiles aimed at U.S. territory across the whole spectrum of their flight path, adopted a new, untrieddevelopment and acquisition strategy, announced U.S. withdrawal from the 1972 Anti-ballisticMissile Treaty, and has deployed an initial national missile defense capability.
The Administration argued these steps were necessary in response to growing concerns overthe spread of weapons of mass destruction and their means of delivery, especially on the part of ahandful of potentially hostile states and terrorists. In addition, they asserted that U.S. deterrencetheory has outlived its usefulness and that conventional or nuclear deterrence could not be reliedupon to dissuade unstable leaders in rogue states.
Critics, however, take issue with assertions that the threat is increasing, citing evidence thatthe number of nations seeking or possessing nuclear weapons has actually declined over the past 20years. Moreover, they argue that the technology for effective missile defense remains immature, thatdeployment can be provocative to allies, friends, and adversaries, and it is a budget-buster thatreduces the availability of funds to modernize and operate U.S. conventional military forces. Theyargue especially that some major powers view U.S. missile defense as an attempt at strategicdomination and that other, such as China, will expand their missile capabilities in response.
This report will be updated as needed.

subsections: section_title: Most Recent Developments
paragraphs: For FY2006, the Bush Administration requested $8.73 billion for the Missile DefenseAgency (MDA) budget. This includes $3.3 billion for the Ground-Based Interceptor (GBI) program,currently being deployed in Alaska and California. The House-passed defense authorization bill( H.R. 1815 ) provides $8.83 billion, an increase of $100 million for the ground-basedmissile interceptor program. The Senate-passed authorization bill approved $8.73 billion for MDA( S. 1042 ) and similarly specified that $100 million of the funds provided for theMidcourse Defense Segment be used to enhance the ground-based missile interceptor test program.The House-passed defense appropriations bill ( H.R. 2863 ) includes $8.58 billion forMDA. It too specifies an additional $100 million for ground-based missile defense interceptortesting. The Senate-passed appropriations bill provides $200 million more for the ground-basedmissile defense interceptor program and $65 million for the Israeli Arrow system.
Although missile defense remains strongly supported, Congress and others have raisedquestions and concerns over several programs, including the Airborne Laser, the SSTS (SpaceSurveillance and Tracking System), and the BMD System Interceptor program. Some concerns alsoremain over significant flight test delays in the ground-based system being deployed in Alaska andCalifornia.
Recent milestones reported by MDA include a successful intercept by the Navy's sea-basedmissile defense program, a successful flight test of the revamped Theater High Altitude AreaDefense (THAAD) system, a successful flight test of the ground-based mid-course defense (GMD)interceptor, and deployment of the 10th operational interceptor of the GMD system.
section_title: Overview
paragraphs: [author name scrubbed] & Amy A. Woolf, Specialists in NationalDefense
subsections: section_title: Issues for Congress
paragraphs: In July 2001, the Bush Administration presented to Congress the outlines of its proposedapproach to missile defense. The Bush Administration's plan differed significantly from theapproach pursued by the Clinton Administration. The issue for Congress remains whether toapprove or modify the Bush Administration's proposed approach for missile defenses. In general,Congress has supported the President's approach, making some adjustments in programsexperiencing technical problems and reducing funding for programs that Congress was not yetwilling to commit to for early deployment purposes.
In December 2002, the Administration announced its decision to begin fielding initial missiledefense capabilities in 2004-2005. An initial national missile defense capability was declared withthe deployment of eight interceptors in Alaska and California at the end of 2004.
section_title: Scope of Report
paragraphs: This report provides background information on the Bush Administration's proposedapproach, and discusses key issues relating to it. Key issues raised in the next section include:
Ballistic Missile Proliferation : Which countries of concern possess or aredeveloping missiles that might threaten the United States, its military forces, or its friends and allies?What range of missile threats might U.S. missile defenses be required to counter in the near andmid-term?
Technology issues: Will the United States be able to develop and deploymissile defenses that can intercept missiles of all ranges and at all phases of their flights? If not, cana partial system be overcome even by rogue states? What are the key technological challenges? When might the research and development program give way to a deployment program? WillDOD's acquisition policy affect the planned incremental deployment strategy?
The latter sections of the report provide background information on the various parts of theAdministration's proposed missile defense program. It includes program and budget data, and keytechnical challenges faced by the programs. The report concludes with a summary of congressionalaction on the missile defense budget.
section_title: Missile Defense Prior to the Bush Administration
paragraphs: The United States has pursued the development of missile defenses for more than 50 years. Since the Reagan Strategic Defense Initiative (SDI) was launched in FY1985, the United States hasspent more than $85 billion on missile defense programs and studies. Missile defense has provento be a challenging and elusive endeavor. Moreover, the question of whether the United Statesshould deploy extensive defenses to protect against ballistic missile attack has been one of the mostdivisive political and national security issues of this generation. 
The demise of the Soviet Union and the debate over the emergence of ballistic missile threatsfrom other nations changed the nature of the debate. For many, concerns about nuclear stabilitybetween the United States and Russia have receded as the two nations expanded their areas ofcooperation and improved their relationship, especially in the U.S. lead war on terrorism. Instead,many now focus on concerns about a possible attack from an adversary who possesses only a fewmissiles and may not be deterred by fear of U.S. retaliation. Without a missile defense capability,some argue, the United States itself may be deterred from using its conventional forces to protectU.S. allies and friends. Similarly, the United States might be unable to combat aggressive orprovocative actions on the part of "rogue states" armed with chemical, biological, or nuclear capableballistic missiles. (1) Eventerrorist acquisition of ballistic missiles armed with weapons of mass destruction is today part of thepolicy debate.
The Clinton Administration responded to this changing international security environmentby pursuing the development and deployment of defenses that would protect U.S. allies and forcesin the field from attack by shorter and medium-range ballistic missiles (theater missile defense:TMD). It also sought to develop for deployment a limited system to protect U.S. territory fromattack by longer-range ballistic missiles (national missile defense: NMD). Its plans for NMD wouldeventually have conflicted with the terms of the 1972 Anti-ballistic Missile (ABM) Treaty with theSoviet Union, which limited the United States and Soviet Union (now Russia) to a single, land-basedsystem for defense against long-range ballistic missiles. The Administration sought to preserve thebasic framework of the ABM Treaty by negotiating modifications that would have permitted thedeployment of a limited, land-based NMD site in Alaska. The Clinton Administration decided,however, that it would not proceed to deploy the site after failures in the flight test program and othertechnical concerns raised questions about the readiness of the technology.
section_title: Bush Administration's Proposed Approach
paragraphs: The Bush Administration sharply altered the debate over missile defense. In severalpre-election speeches, President Bush indicated that he would pursue the development oftechnologies that could be deployed on land, at sea, and in space to protect the United States, itsallies, and its forces overseas from ballistic missile attacks from rogue nations. President Bush alsostated that the United States would have to "move beyond the constraints" of the ABM Treaty. Heemphasized that "Russia is not our enemy," and, therefore, Russia should not be concerned aboutU.S. deployment of missile defenses. Instead of seeking to modify the ABM Treaty so that theUnited States could deploy limited missile defenses, the President said "we need a new frameworkthat allows us to build missile defenses to counter the different threats of today's world." (2) 
The Administration began to outline the details of its plans for missile defenses in July 2001,after submitting its amended defense budget for FY2002 to Congress. In that budget, theAdministration requested $8.3 billion for missile defense, an increase of $3.1 billion or 61 percentover the amount Congress funded for FY2001. The Administration stated that it would explore abroader range of technologies and basing modes, "including land, air, sea, and space-basedcapabilities that had been previously disregarded or inadequately explored." However, as isdescribed in more detail later in this report (see Table 1 ), the Administration appears to haveessentially increased funding evenly for each of the missile defense and sensor technologies alreadyin the defense budget. From a funding and programmatic perspective, the Administration did notappear to give increased priority to any particular program or introduce any major new researchdirections for FY2002 beyond what the Clinton Administration was already pursuing, except toaccelerate the process and integrate key components. A similar argument was made with respect tothe FY2003 missile defense budget of $7.8 billion.
In its missile defense program, the Bush Administration eliminated distinctions betweentheater and national missile defenses (TMD and NMD). Instead, according to General Kadish, thedirector of MDA (formerly the Ballistic Missile Defense Organization (BMDO)), the Administrationhas "developed a research, development, and test program that focuses on missile defense as a singleintegrated BMD system." Furthermore, the objective of this program is to "aggressively evaluateand develop technologies for the integration of land, sea, air, or space-based platforms" and todevelop and deploy a global system of "layered defenses, capable of intercepting missiles of anyrange at every stage of flight -- boost, mid-course, and terminal." (3) 
Administration officials have highlighted two primary benefits of layered defenses. First,layered defenses would seek to provide the United States with more than one opportunity to targetan attacking missile, thus arguably increasing the chance of shooting it down. (A critique of thelayered defense concept is outlined in the section on Technology and Other Challenges.)
Second, the layers could complicate an attacker's ability to defeat the overall system. Thisis because countermeasures, which are intended to confuse or overcome defenses, that might beeffective in one phase of a missile's flight might not work in other phases.
The Bush Administration has emphasized that its missile defense program will concentrateon "robust research and development" into a wide range of missile defense technologies. Unlike theClinton Administration, the Bush Administration has not yet identified an architecture (a detailedmissile defense system with specific objectives and capabilities) that it will seek to deploy norestablished a schedule for the development and deployment of any particular system or element; but,a clear underlying objective is the early deployment of a defense designed against missiles aimed atU.S. territory. Because it has not identified the types of technologies or the numbers of interceptorsand radars that it intends to deploy, the Administration will not provide any costs for the missiledefense program or system. It emphasizes that cost estimates are premature under the new approach.
Administration officials have stated that this research and development effort is "designedto develop effective systems over time ... and to deploy that capability incrementally." The programenvisions the deployment of "different combinations of sensors and weapons" when thesetechnologies "are proven through robust testing." These technologies could then be replaced by moreeffective or advanced systems when they become available. This approach is called an evolutionaryacquisition strategy. This strategy differs from the way in which most military acquisition programsoccur. It will likely be the subject of increased scrutiny. An analysis of this strategy and some of itsimplications follows in a subsequent section of this report.
During congressional testimony in July 2001, Deputy Secretary of Defense Wolfowitz statedrepeatedly that the United States would not violate the ABM Treaty, but that the Treaty stood in theway of the Administration's missile defense efforts. He noted that some of the tests or activitiescould "bump up" against the limits in the Treaty in "months not years." (4) However, the BushAdministration also stated that the United States would have liked to reach an agreement with Russiathat would allow these tests, and the eventual deployment of extensive missile defenses, to proceedwithout concern for the Treaty limits. 
At a meeting in Italy in July 2001, President Bush and Russia's President Putin agreed thatthe two nations would hold discussions that focused on both offensive weapons and defensivesystems. Some interpreted this agreement to mean that the two nations would begin negotiations onnew treaties that would limit offensive nuclear weapons and missile defenses. Administrationofficials stated clearly, however, that these were not negotiations, but consultations. They also statedat that time the Administration did not plan simply to seek modifications in the ABM Treaty, but itwould not allow the Treaty to prevent research and development toward deployment even if thatultimately meant U.S. withdrawal from the Treaty. (5) Rather, the Bush Administration sought to convince Russia thatthe ABM Treaty was no longer relevant and that the two nations should agree to set it aside andreplace it with a new framework for their relationship. According to some reports, the United Stateswould share information about missile defense developments with Russia, but it would not acceptany limits on research, development, testing, or deployment of its systems. Russia, however, did notaccept the U.S. approach, and, on December 13, 2001, President Bush announced that the UnitedStates would withdraw from the Treaty. Actual withdrawal from the 1972 ABM Treaty occurredJune 13, 2002. The Administration announced it had a specific plan for deploying an initial missiledefense capability on December 17, 2002.
section_title: Key Issues
paragraphs: [author name scrubbed], Analyst in National Defense
subsections: section_title: Ballistic Missile Proliferation
paragraphs: Overview. Currently, Russia and China are theonly two countries that could attack the United States with intercontinental ballistic missiles(ICBMs). Although other countries with short and medium range missile programs may aspire tojoin this club, there are factors other than scientific and infrastructure to consider. Variables suchas the availability of financial resources, political will, availability of foreign material and technicalassistance, and the affects of non proliferation and export control regimes all play a role in missiledevelopment. In this regard, countries discussed here other than Russia and China should beconsidered as potential future threats outside of their respective regions. Within their respectiveregions however, these countries, along with Russia and China, will present an ever increasingproliferation challenge to U.S. forces, friends, and allies. 
Ballistic missile proliferation has continued steadily over the past two decades presenting avariety of security challenges to the United States. The number of countries with operationallydeployed ICBMs that could strike targets in the United States remains relatively small. There is,however, a fairly widespread and growing capability to launch shorter range missiles and a slowlyevolving capacity to launch medium range missiles. (6) These short to medium range missiles could not only threaten U.S.forces on a regional basis but could also serve as a precursor for the development of longer rangemissiles over the course of the coming decades. The transition from short to medium range missilesto ICBMs is more a matter of technical expertise than of technology. The principal hurdles todeveloping longer range missiles are manufacturing larger propulsion systems and designing amissile with more than one stage. With an existing short or medium range ballistic missileinfrastructure, overcoming these hurdles becomes an issue of having an experienced and qualifiedscientific and engineering staff. If a country does not have this expertise domestically, it can beimported. The United States routinely monitors ballistic missile development and deployment trendsin a number of critical countries. The countries listed below are those critical countries addressedin the 2002 National Intelligence Estimate (NIE) on Foreign Ballistic Developments and the BallisticMissile Threat Through 2015.
Russia. Russia has the most significant ballisticmissile inventory of all countries of concern. Russia currently has approximately 700 ICBMs (7) capable of delivering over3,000 nuclear warheads of various yields. (8) Russia also maintains a number of ballistic missile-capablesubmarines equipped with approximately 200 launchers that could deliver up to 900 nuclearwarheads. (9) Despite theseseemingly significant numbers, the Russian Strategic Nuclear Forces have been in critical declineover the past decade due to a variety of internal and external factors. 
Because of slower than anticipated development and also in response to the United Stateswithdrawal from the ABM Treaty, the Russian government has slowed the production of its newSS-27 ICBM (START II compliant with one nuclear warhead) and will instead retain a significantnumber of its older SS-18 and SS-24 ICBMs (each capable of carrying 10 multiple independentreentry vehicles (MIRVs)) that were destined to be destroyed under START II ceilings. Russia willretain 154 liquid-fueled SS-18 Satan heavy ICBMs and 36 SS-24 Scalpel ICBMs that were supposedto be eliminated by 2007 under the provisions of START II. (10) Russia's SS-27 Topol-M ICBM was first deployed in 1997 and Russia had deployed 23 SS-27s in silos as of the end of2000. (11) Althoughdesigned to carry one warhead, experts believe that with modifications the SS-27 could carryanywhere from 3 to 6 nuclear warheads. Russia claims to have developed missile defensecountermeasures for the SS-27 allowing the SS-27 to penetrate any known missile defense. Suchcountermeasures could include global positioning technology and independent warhead maneuveringcapability. It is important to note that independent sources have not substantiated Russian claimson the SS-27's penetration capabilities. Over the next five years, the Defense Intelligence Agencybelieves that Russia will focus its limited resources on the SS-27 program, the SS-26 short rangeballistic missile (SRBM), and the submarine-launched SSN-23 and Bulava-30 ballistic missiles. (12) 
China. China's current ICBM force consistslargely of liquid propellant, single warhead, silo-based missiles. Approximately 20 of these missilesare CSS-4 missiles that can reach targets within the United States. About 12 CSS-3 ICBMs aredeployed and are most likely intended as a deterrent force to Russia, Pakistan, and China. (13) China also has a numbermedium-range JL-1 submarine launched ballistic missiles (SLBMs). Concerned about thesurvivability of their ballistic missiles, China is focusing on the development of mobile, solidpropellant ICBMs. The Intelligence Community projects that by 2015, most of China's land-basedICBMs will be mobile. (14) 
China continues to develop solid-fueled DF-31 ICBMs for both silo and mobile basing, aswell as for submarine deployment. China has tested CSS-5 medium-range ballistic missiles(MRBMs) with dummy warheads or what the Pentagon calls "penetration aids" designed to defeatmissile defense systems. China is assessed to be capable of developing multiple reentry vehicles(MRVs) for its CSS-4 missiles in the next few years but MRV development for its new mobileICBMs and SLBMs would face significant technical hurdles and would be extremely costly. (15) China continues to deployshort-range CSS-6 and CSS-7 missiles across the Taiwan Strait. U.S. intelligence estimates thatthere are about 350 Chinese missiles deployed within about a 7Â½ minute flight time of Taiwan. Recently, China has offered to reduce the numbers of deployed missiles if Taiwan scales back itsarms purchases from the United States. China has also exported missile technologies to Iran,Pakistan, North Korea, and Saudi Arabia.
Iraq. Western Intelligence believes that Iraq hasupwards of 20 Al Hussein SRBMs and about a dozen transporter, erector, launchers (TELs) inbreach of 1991's UN Security Council Resolution (UNSCR) 687. (16) Other organizations, suchas the London-based Institute for Strategic Studies, suggest that this number could be closer to adozen or fewer missiles. (17) Iraq has continued its short-range missile program, which ispermitted under UNSCR 687, but U.S. and British Intelligence believe that they are working onextending the range of these missiles in excess of the 150 km range permitted. Iraq has also rebuiltpreviously-destroyed facilities and constructed new facilities designed to produce solid propellantsand to test missile engines with ranges in excess of 1,000 kms. 
Iran. Iran has one of the largest missileinventories in the Middle East. Iran has a few hundred SRBMs consisting mostly of SCUD-Bs,SCUD-Cs, and Chinese CSS-8 missiles. Iran has also successfully tested and deployed a smallnumber of Shahab-3 MRBMs that could strike targets in Israel, Turkey, and most of Saudi Arabia.The Shahab-3 is based on the North Korean No Dong missile and is believed to have a range of1,300 kms. (18) Iran hasalso publically acknowledged the development of the Shahab-IV as a ballistic missile (laterreclassified as a space launch vehicle (SLV)) with an estimated range of 2,200 kms. (19) Iran is also believed to bedeveloping a Shahab-V with an unspecified range. In all cases, Iran's continuing development of itsmissile program will rely heavily on Russian, Chinese, and North Korean assistance. Despite Iran'scurrent efforts, most U.S. intelligence agencies believe that Iran will not be able to launch anICBM/SLV until the later half of this decade while one agency says that a successful test launch isunlikely prior to 2015. (20) 
North Korea. North Korea's recent actions inrelation to the Agreed Framework and possible "reconsideration of the missile testing moratorium"could foreshadow their resumption of missile testing. The two-stage Taepo Dong 2, which somebelieve could deliver a several hundred kilogram nuclear payload to Alaska, Hawaii, and parts of thecontinental United States may be ready for flight testing in the near future. (21) If North Korea cansuccessfully integrate a third stage, this could boost the Taepo Dong's range to 15,000 km --sufficient range to strike all of North America. (22) North Korea also has hundreds of SCUD and No Dong missilesthat pose a significant WMD threat to U.S. and allied military forces in the region. North Koreahas continued to export ballistic missiles and associated technology, most notably to Pakistan andYemen. On December 11, 2002 the Spanish military intercepted 15 SCUD missiles at sea boundfor Yemen. This was later determined to be a legal shipment and was allowed to proceed. NorthKorea is also believed to be training missile engineers and technicians, most notably Syrian, in thedomestic production of SCUD missiles. 
India. India continues their aggressive domesticdevelopment of ballistic missiles, primarily to establish a nuclear deterrent to Pakistani first use ofnuclear weapons and as a hedge against a confrontation with China. (23) The Prithvi I, asingle-stage, liquid fueled, road-mobile missile, is currently India's only deployed ballisticmissile. (24) India alsocontinues to develop the Prithvi II, a 250 km SRBM. India has tested the Agni-series of MRBMwith a reported range of 2,000 km. These Agni-series of missiles will likely become operational inthe next few years and will become the mainstay of India's MRBM forces. (25) India has a domestic spacelaunch vehicle program referred to as the Surya program. Intelligence sources believe that Indiacould convert this SLV into an ICBM within one to two years after the decision had been made todo so. (26) India is actively developing the Sagarika SLBM and is attempting to buy or lease nuclear submarines withthe intent of modifying the submarines to accommodate SLBMs.
Pakistan. Pakistan's pursuit of missile-deliverednuclear weapons is a considered by many experts as a deterrent to India's nuclear program as wellas their numerically-superior conventional forces. (27) Like India, Pakistan is developing an indigenous ballistic missileproduction capacity and has a variety of missiles. The short range (80 km) Hatf I is a simple solidpropellant missile designed not only for domestic use but also for export. The Hatf III (modifiedChinese M-11 missile) is a single-stage, solid propellant missile with a range of at least 300 kms. Pakistan also has a number of No Dong missiles (renamed Ghauri) from North Korea with a rangeof 1,500 km. Pakistan is developing and testing Ghauri 2 and Ghauri 3 missiles with reported rangesof 2,000 and 3,000 kms, respectively. (28) Pakistan is also developing the road-mobile, two-stage solidpropellant Shaheen II with a reported range of 2,500 kms. (29) 
Libya. U.N. sanctions from 1992 to 1999 arebelieved to have severely limited Libya's ability to obtain the requisite expertise, materials, andequipment to continue its development of MRBMs and ICBMs. (30) Since the removal ofsanctions in April 1999, Libya has actively attempted to refurbish its aging SCUD force as well asobtain complete, long-range missile systems through a variety of foreign suppliers. Reports suggestthat Libya may have received No Dong MRBMs from North Korea, but this has not been confirmedby Western intelligence sources. (31) Libya may be working on its Al Fatah missile that it claims hasa 1,000 km range (U.S. intelligence believes the range is closer to 200 kms.) but this missile has notyet been tested. (32) 
Syria. Syria possesses an extensive mobileSCUD-B, SCUD-C, and SS-21 SRBM arsenal. (33) These systems could allow Syria to strike deeply into theterritories of potential regional adversaries Israel, Iraq, Turkey, and Jordan. (34) Although Syria has notshown any overt interest in acquiring longer-range missiles, it is possible that as regional securityprospects continue to deteriorate, Syria may attempt to acquire longer-range systems such as the NoDong MRBM.
section_title: Technical Issues & Acquisition Strategy
paragraphs: Hit-to-Kill. ( [author name scrubbed], Specialist inNational Defense ) The concept of kinetic kill or hit-to-kill has been a primary focus of the missiledefense program since the conception of the SDI in the early 1980s. Previously, the United Statespursued missile defense concepts that employed nuclear weapons as interceptors. More conventionalexplosive warheads were used to develop the PAC-2 system used in the Persian Gulf war againstIraqi Scud missiles. Advanced and exotic concepts, such as various lasers, were largely deemedimpractical during the late 1980s and early 1990s.
A kinetic kill interceptor would seek to destroy its intended target through a direct collisionat relatively high speeds. The force of the impact would then destroy the attacking missile orwarhead, render it inoperable, or divert it from its intended target. With such an approach, anear-miss has the same practical affect as a large distance miss: the target is not destroyed. 
Kinetic kill as a concept for destroying short- and medium-range ballistic missiles appearsto be in the process of proving itself. After a string of failed intercept tests, the THAAD programbegan a series of successful tests. Barring major, unforseen technical or engineering problems, itappears that a kinetic kill warhead for THAAD can be developed. The same is true of the PAC-3system. The next generation Patriot interceptor seems to be proving the concept of kinetic kill forshort-range missile defenses, despite the most recent test failures in February 2002.
The key question remaining, however, centers around levels of effectiveness, particularly inwartime. Under test-range conditions, most military systems perform better than they do in anoperational environment. The Patriot system used in Desert Storm is a notable example. Prior tothe war, Patriot successfully intercepted 17 of 17 very different targets under a variety of test rangeconditions. Patriot encountered a vastly different operational environment when deployed, and itssuccess or failure during the war is still debatable, and, according to experts, probably unknowable.
Kinetic kill as a concept for destroying long-range ballistic missiles is even more problematicat this stage. There is no unambiguous, empirical evidence to support the contention that kinetic killfor ICBM defense will work. Missile defense advocates argue that since the mid-1980s, a string ofsuch tests have occurred with varying degrees of success; some have failed to achieve interception,while others were deemed successful. 
But in almost every case, post-test doubts have been raised. Critics have charged that testresults over the past two decades have been exaggerated by false claims of success and promises ofperformance that later proved false. Many tests were proven to have had their targets significantlyenhanced to ensure the likelihood of success.
Some missile defense advocates say this may be true. But kinetic kill for ICBM defense iscomparable to where kinetic kill was for systems such as PAC-3 several years ago. They maintain,therefore, that continued development, and especially more realistic testing, is needed to ensure thatthe kinetic kill concept for long-range missiles can eventually be deployed.
Layered Defenses. ( [author name scrubbed], Specialistin National Defense ) The concept of layered defense, which dates back to at least the 1960s, andwas developed more systematically in the 1980s, envisions deploying several missile defensesystems, each designed to intercept an attacking missile or warhead at a different stage of its flighttrajectory. The concept arguably would allow for multiple intercept opportunities. Although thispresents the possibility that one element of the system may not work as intended, proponents arguethat multiple intercept opportunities significantly increase the chance that an attacking missile orwarhead will be destroyed.
Proponents of layered defenses argue that each layer is able to attack a different vulnerabilityof the attacking ballistic missile and that, because each layer is statistically independent of everyother layer, the probability of a warhead getting through all of the layers (1 to N) can be given by asimple multiplication of the probabilities of surviving each independent attack. (35) This analysis wouldreadily lead to a conclusion that a defense with three layers, for example, might let extremely fewmissiles or warheads get through.
Other analysts, however, would argue that this is a wrong conclusion. In the first place, thereis no empirical evidence of an air defense system with a probability of intercept (P i ) much greaterthan about 30 percent (or 0.3). So one might conclude more realistically that the probability that anattacking missile or warhead will survive is closer to 34 percent. (36) Moreover, it isargued, (37) even if oneassumes that each layer is 90 percent effective, the layered defense model fails because the layersare not statistically independent for at least two reasons:
Each attacking warhead or missile must encounter each of the layers in order,so the performance of one layer will affect the performance of the next layer and so on. For example,if the first layer underperforms because some countermeasure is unexpectedly successful, then thesecond layer will be required to deal with more simultaneous targets than expected; if one missileor warhead avoids interception, that may mean that circumstances are favorable for the next missileto get through also. Even if each layer is over designed by a factor of about 2, failure of one layercan still lead to saturation of the next. For example, if we expect the terminal layer to have to handle10 warheads, we might design it to handle 20, but if earlier layers then fail so that the terminal layeris presented with 30 targets, at least 10 warheads will get through to their intended destination evenif the terminal layer works perfectly. The failure of an early layer would thus result in the collapseof the missile defense system: the layered 'pyramid' defense is balanced on its vertex, rather than setfirmly on its base.
Until a layered defense has been tested under realistic conditions, when it mustengage warheads nearly simultaneously in each layer, it is unrealistic for defense planners to assumethat there are no problems of command and control among the layers, and that unknown variablesdo not operate to degrade the system in unpredicted ways. Such a test would be expensive anddifficult to achieve, requiring the multiple simultaneous launch of severalICBMs.
The probability of an attacking warhead surviving intercepts by three "correlated" layerscannot be known without making assumptions about the mechanism of the correlation andnon-independence of the layers. In general, critics conclude the performance of the system may beno better than the performance of the best layer, and then only if that layer is not saturated by thesheer numbers of missiles, warheads, or countermeasures.
Layered defense proponents are likely to understand, and perhaps agree, with many of thesepoints. But supporters will respond by suggesting these issues can be adequately addressed in thedesign of a missile defense architecture and adjustments made during its development (see below).
Acquisition Strategy & Congressional Oversight. ( Gary Pagliano, Specialist in National Defense ) Some observers, particularly critics of the missiledefense program, have expressed concern that the Administration's overall approach for managingthe program could hinder Congress's ability to conduct effective oversight of it. Three areas of theAdministration's management approach are at issue: The first concerns the Administration's planto use evolutionary acquisition with spiral development to develop and acquire missile-defensesystems. The second concerns a DOD directive that exempts the missile defense program fromcertain reporting requirements that are normally applied to major defense acquisition programs. Thethird concerns a decision to classify certain missile defense testing and program information.
The Administration and its supporters argue that these three developments are needed to helpthe program proceed expeditiously and to help prevent potential adversaries from learning how toevade or overcome U.S. missile-defense systems when they are deployed. Critics argue that thesethree factors could reduce Congress's ability to understand, track, and thereby conduct effectiveoversight of the Administration's missile defense program. Each of these three developments isdiscussed below.
Evolutionary Acquisition with Spiral Development. ( Gary Pagliano, Specialist in National Defense ) In presenting its new missile defense program toCongress in 2001, the Administration announced that missile defense systems would be developedand acquired under a relatively new approach called evolutionary acquisition with spiraldevelopment, or spiral development for short. As discussed in another CRS report, (38) spiral development is anoutgrowth of the defense acquisition reform movement of the 1990s, and represents a departure fromthe traditional DOD approach for developing and acquiring major weapon systems. Spiraldevelopment is aimed at achieving certain widely accepted defense-acquisition goals, including thefollowing: (1) getting usable increments of a weapon capability into service sooner; (2) mitigatingtechnical risk in acquisition programs involving new or emerging technologies; (3) taking advantageof user feedback in terms of determining how to modify and improve the system; and (4) facilitatingthe incorporation of new technologies into the system design during the system's life cycle.
Missile defense was the first major weapon acquisition program to be publicly linked withspiral development. DOD officials, however, have stated that they want spiral development to bethe new "default" (i.e., standard) acquisition strategy for major weapons acquisition programs, andhave since announced their intention to apply spiral development to other major weapon acquisitionprograms, such as the Navy's DD(X) next-generation surface combatant program.
Under an evolutionary acquisition strategy, a basic version of a weapon system is developedand fielded with the intent of subsequently developing and deploying more capable versions of thesystem as technology and requirements are further refined. A critical aspect of evolutionaryacquisition is spiral development, under which the various elements of a weapon system evolveincrementally over time in an iterative manner. Instead of attempting to develop a system that will,upon first deployment, fully satisfy a detailed military requirement, systems under an evolutionaryacquisition strategy would be developed, tested, deployed, and modified in a cyclic process that, inprinciple, would permit weapons developers to incrementally work toward a final systemconfiguration that is eventually capable of meeting its required objectives.
A distinct characteristic of evolutionary development is a reduced ability, particularly at theoutset of a program, to define what the deployed system might look like at various points in thefuture. Rather than attempting to define final configuration at the outset, evolutionary developmentconsciously treats this issue as an open question to be addressed over time as elements of the systemare developed, deployed, evaluated, and modified. In this sense, the Administration's proposedmissile defense effort is more of an evolving concept than a typical military system in development.
The Administration's missile defense plan would apply evolutionary acquisition and spiraldevelopment to an entire family of system development efforts related to the common mission ofmissile defense. Under the Administration's plan, missile defense systems would be built, tested,deployed, and evaluated incrementally. The final missile defense system or architecture -- that is,the numbers and characteristics of the land-, sea-, air-, and space-based system involved -- wouldbe determined gradually over the course of several years. During this period, systems capable ofperforming similar portions of the missile defense mission (i.e., the boost phase, the midcoursephase, or the terminal phase) would be in implicit competition with one another for places in thefinal system configuration.
The Administration's plan to employ this acquisition strategy for missile defense is consistentwith its view that missile defenses are urgently needed. The Administration argues that deployingmissile defenses sooner with less capability than later versions is desirable because any improvementin U.S. missile defense capabilities would complicate enemy planning and thereby strengthendeterrence against ballistic missile attacks. The Administration also argues that the strategy isappropriate for weapon acquisition programs, such as missile defense, where the fundamentaltechnologies involved are less technically mature than they are for well-established types ofweapons, such as aircraft and ships.
A major consequence of the Administration's proposed evolutionary acquisition strategy isthat the missile-defense program would not feature the familiar phases and milestones of thetraditional DOD acquisition system. Another consequence, already reflected in DOD testimony, isthat BMDO cannot provide Congress with a description of its final missile defense architecture, thecapabilities of any near- or longer-term system, the specific dates by which most elements of theemerging architecture are to be tested and deployed, an estimate of the eventual total cost of themissile-defense program, or estimates of the amounts of funding that the program will require inindividual years beyond FY2002. Lt. Gen. Ronald Kadish, Director of BMDO (now MDA), statedthe following to the Senate in July 2001 in introducing the Administration's missile-defense plan
But before I proceed to describe the newprogram in detail, I would like to make clear what this program does not do. It does not define aspecific architecture. It does not commit to a procurement program for a full, layered defense. Thereis no commitment to specific dates for production and deployment other than for lower-tier terminaldefense systems....
First, we are recommending a broad, flexibleapproach to RDT&E that allows us to explore multiple development paths and to reinforce successbased on the best technological approaches and the most advantageous basing modes in order tohedge against the inherent uncertainty of the ballistic missile defense challenge. Second, we arerecommending an acquisition approach that is evolutionary, one that will allow us to field systemsincrementally once they are proven through realistic testing. And third, rather than committing toa single architecture as we have done in the past, we will deploy over time different combinationsof sensors and weapons consistent with our national strategicobjectives....
This robust RDT&E program aims todemonstrate what does and does not work. Those activities showing the greatest promise willreceive greater resource emphasis. Our progress will inform an annual high-level decision-makingprocess that will steer the BMD program in the most promising direction, taking into accountoptimal approaches and the most reliable information on costs, allowing informed research,production, and deployment decisions....
The business of missile defense requires copingwith a number of technological, developmental, acquisition, and threat uncertainties. For this reason,I cannot tell you today what exactly the system will look like 15, 10, or even five years from now. This system will take shape over time. We do not intend to lock ourselves into a highly stylizedarchitecture based on either known technologies or hoped for advances in technology that will takea decade or more to complete. We intend to go beyond the conventional build-to-requirementsacquisition process....
Specific system choices and time lines will takeshape over the next few years through our capability-based, block approach. We will increase ourcapability over time through an evolutionary process as our technologies mature and are proventhrough testing. The block approach allows us to put our best, most capable technologies "in play"sooner than would otherwise be possible. We have organized the program with the aim ofdeveloping militarily useful capabilities in biannual blocks, starting as early as the 2004-2006 timeframe....
We must deviate from the standard acquisitionprocess and recognize the unprecedented technical challenges we are facing. We do not have major[missile] defense acquisition programs in the FY2002 budget. We do not have program activitieswith traditional fixed milestones and clearly marked phases showing the road toproduction.
The new approach to BMD developmentfeatures more streamlined, flexible management through comprehensive and iterative reviews. Wewill establish yearly decision points to determine the status of the available technologies and conceptevaluations in order to be in a position to accelerate, modify, truncate, or terminate efforts in aparticular area. This comprehensive annual review process will also help us make decisions to shapethe evolving systems and allocate resources to optimally support them. (39)
The Administration and its supporters argue that the use of spiral development for the missiledefense program (or other weapon acquisition programs) will not prevent Congress from conductingeffective oversight, and could even improve Congress's oversight ability in some respects, becauseCongress will retain its role in approving each block, or segment, in a spiral development program,and because the information that DOD provides for the block to be approved will be more reliablethan the potentially speculative information it might present under the traditional acquisitionapproach about what the entire program might look like from beginning to end.
Critics of the Administration's plan to use spiral development argue that it could reduceCongress's ability to provide effective oversight by putting Congress in the position of approving thestart of a program whose outlines are only vaguely defined, because the lack of an original estimateof the program's overall quantities, cost, schedule, and cost would deprive Congress, years later, ofa benchmark against which to measure performance of the program, and because the built-inpotential for changes in a spiral development program could make funding projections for spiraldevelopment programs more volatile than funding projections for traditional developmentprograms. (40) 
Exemption from Reporting Requirements. ( GaryPagliano, Specialist in National Defense ) In January 2002, the Secretary of Defense issued amemorandum exempting the missile defense program from certain reporting requirements normallyapplied to major defense acquisition programs (even those that employ spiral development). TheAdministration's stated intent in issuing this directive was to help streamline the management andoversight of the missile defense program and thereby enable it to proceed more expeditiously. Thisobjective is consistent with the Administration's interest in fielding missile defense systems withoutdelay. Critics of the Administration's missile defense program, however, argue that the directive willdeprive Congress of key program information and thereby reduce the ability of Congress to conducteffective oversight of the program. (41) 
Information to Be Classified. ( Gary Pagliano,Specialist in National Defense ) In May 2002, the Administration announced that certain informationabout the missile defense program, including details about developmental tests, will henceforth beclassified, and, therefore would not be released to the public. Administration officials argue thatclassifying the information will help prevent potential adversaries from learning about the technicalcharacteristics of U.S. missile defense systems and using that information to design ballistic missileswith features designed to evade or overcome U.S. defenses. Critics of the decision argue that someof the information the Administration has decided to classify, such as basic details about earlydevelopmental tests, would be of no practical use to a potential adversary, and that theAdministration's actual motive in limiting access to the information is to shield the missile defenseprogram from public scrutiny and criticism. (42) 
section_title: Background on Major Missile Defense Programs
subsections: section_title: Boost Defense Segment
paragraphs: Air-Based Boost. ( [author name scrubbed], Analyst inScience & Technology, and [author name scrubbed], Specialist in National Defense ) The Air-BasedBoost program, more commonly known as the Airborne Laser (ABL), would use a high-powerchemical laser mounted in a modified Boeing 747 aircraft to shoot down theater missiles in theirpowered boost phase of flight. The laser would seek to rupture or damage the missile's booster skinto cause the missile to lose thrust or flight control and fall short of the intended target before decoys,warheads, or submunitions are deployed. The ABL's intended range is several hundred kilometers.Major subsystems include the lethal laser, a high-precision tracking system for keeping the laserbeam on target, and an adaptive optics system that compensates for atmospheric effects to keep thebeam tightly focused.
The ABL program was transferred to BMDO, now the MDA, from the Air Force. The MDAstates there is no current system or architecture envisioned for missile defense, including specificsfor the ABL. But the Director of BMDO, in congressional testimony, has stated that "BMDO willevaluate the most promising projects" for boost-phase defense "to provide a basis for an architecturedecision between 2003 and 2005." 
The most recent Air Force concept envisioned a fleet of seven aircraft. Five of these aircraftwould deploy to a theater to support two 24-hour combat air patrols. These aircraft would bepositioned behind the friendly line of troops and moved closer toward enemy airspace as local airsuperiority is achieved. The most recent cost estimate was $10.7 billion (life cycle costs), whichincludes an estimated $1.6 billion for the current program development and risk reduction phase. 
The contractor team consists of Boeing, Lockheed Martin, and TRW. Boeing is responsiblefor the aircraft and for overall management, including systems integration. Lockheed Martin isresponsible for the beam control systems, including target tracking and atmospheric compensation.TRW is responsible for the lethal laser and for ground support systems. There are numeroussubcontractors.
The system currently under development will attempt its first missile shoot-down test in2005. BMDO states this half-power ABL could be available for deployment as an emergencycapability immediately following lethality demonstrations scheduled for late 2005. If all goesaccording to schedule, this system and the next two could provide an initial operating capability: one aircraft on station, one preparing to arrive on station, and one on ground alert between FY2009and FY2011, depending on the results of additional operational testing.
Congressional concerns about the ABL have centered on two main issues: the maturity of keytechnologies and the concept of operations. First, although proponents contend that the ABL employsmature technology, others characterize key aspects (particularly the atmospheric compensationsystem) as experimental. Critics also claim that the tests needed to resolve this question, which arebeing conducted concurrently with the development of the technology, will not take place until 2005.This date is after a second aircraft is scheduled to be ordered, and just months before the firstshoot-down test. The compressed and concurrent nature of this schedule also is an issue of concern.
The Defense Department's Office of Test and Evaluation informed Congress in its FY2000annual report (January 2001) that the 24-month EMD (Engineering, Manufacturing, andDevelopment) program is "alarmingly short....[the schedule] allows for no technical problems or testfailures, and the many integration and test activities cannot all physically be accomplished in the timeallotted for EMD." However, this schedule is likely to change due to the two year delay for the lethalshoot-down.
Second, there is disagreement about whether the ABL would be operationally effective, evenif its technology performs as planned. The ability of the ABL to destroy enemy missiles at itsintended range depends on a number of factors, including atmospheric conditions between the laserand the target, possible enemy countermeasures, and the worldwide trend towards deployment oflonger-range missiles for theater operations. Possible technical countermeasures include hardeningthe missile casing, spinning the missile, or applying a polished finish to the missile.
In addition, the ability to deploy ABL aircraft during crisis or war will depend on the abilityto provide a relatively safe area of operations through air superiority. It is not clear whether enemyforces would wait for this to happen and render their ballistic missile forces more vulnerable, or seeincentives to launch their missiles before ABL systems were deployed, or whether an opponentmight choose to wait out a crisis because a force of ABL aircraft probably would not be deployedon 24-hour combat patrols indefinitely.
Space-Based Boost. ( [author name scrubbed], Specialistin Science & Technology Policy ) The mission of the Space-based Boost intercept portion of theprogram is to develop the capability of shooting down ballistic missiles of any range in their boostphase (i.e., before the missiles have released their payload) from platforms located in orbit. Twoconcepts are under development: a space-based laser (SBL) and space-based kinetic weapons. Bothconcepts have been under development to varying degrees since before SDI in the early 1980s. Congressional funding support for this portion of the program is waning.
In FY2002, the Bush Administration had requested $170 million for space-based laserdevelopment, with much of that directed toward the development of an Integrated Flight Experiment,to be conducted in space and initially scheduled for 2012, and the construction of a test facility tobe located at Stennis Space Flight Center. However, Congress, concerned that the technology wasnot mature enough to warrant the development of the flight experiment at this time, appropriatedonly $30 million for the program. As a result, the Integrated Flight Experiment (which was projectedto cost between $1 billion and $3 billion) and the test center were cancelled. The BushAdministration's FY2003 request for the space-based laser was $34 million, and directed primarilyat reducing technical risks associated with key components (the megawatt hydrogen-fluoride laser,mirrors, beam controls, pointing/tracking/fire controls, etc.). Congress reduced the request by $10million in its FY2003 appropriations. 
The space-based kinetic energy component of the space-based boost phase intercept portionof the program is designed to further develop the key component technologies including the kinetickill vehicle, boosters, sensors, battle management and control, and platform integration. Development work and experiments are to help reduce the technical risks and lead to a designdecision in FY2006 or later. This element was a new start in FY2002 and received $23 million. TheBush Administration requested $53million for FY2003 and had proposed major increases in theprogram in the out-years. Congress cut the request by $50 million. In its appropriations report, theHouse Appropriations Committee stated that greater emphasis should be placed on accelerating themanufacture of existing systems, such as the PAC-3, and on accelerating the development of othermore mature technologies.
There are a number of issues associated with space-based boost phase intercept. Any suchsystem could also function as a anti-satellite weapon, an issue that remains highly controversial. Thedesirability of stationing weapons in space generates differing opinions. Also, the technical hurdlesassociated with space-based interceptors -- especially lasers, with their weight, size, and reliabilityconstraints -- are difficult. Feasibility is not yet certain, hence the need for the demonstrationprograms. At the very least, how long it will take to overcome those hurdles and at what costremains uncertain. Although no longer a constraint, when the ABM Treaty was in force, testing anddeploying these systems in an ABM mode had been prohibited.
Sea-Based Boost. ( [author name scrubbed], Specialistin National Defense ) The Sea-Based Boost program was created by the Bush Administration in2001 as part of its new missile defense program. The general idea of using sea-based missiles tointercept enemy ballistic missiles in their boost-phase, however, goes back several years. Thesea-based boost-defense concept is of potential interest because forward-deployed Navy shipsoperating off the coasts of other countries might be close enough to certain ballistic missile launchsites of concern for high-speed, high-acceleration, ship-launched interceptors to fly inland from theship and intercept enemy ballistic missiles during the boost phase.
The sea-based boost-defense concept appears most feasible for use against missiles launchedfrom sites that are close or somewhat close to international waters, since this would reduce thedistance that the interceptor would need to fly to reach the enemy missile and thereby increase thechance that the interceptor would reach it during its boost phase. The concept might thus have themost potential for intercepting missiles launched from countries such as North Korea, Libya, orperhaps Iran. The concept would appear to offer little potential for intercepting long-range Russianor Chinese missiles, whose launch sites are located deep inland, because these missiles are morelikely to complete their boost phase before a ship-launched interceptor (even one with a high-speed,high-acceleration booster) could reach them.
Although the Sea-Based Boost program is not yet well defined, a robust sea-based boostsystem would likely require an interceptor missile with:
a much higher maximum speed, or burn-out velocity (perhaps 6 to 8 kilometersper second [kps]) than that of the SM-3 interceptor missile now being developed for the Sea-BasedMidcourse system (which has a maximum speed of a bit more than 3 kps);
a high rate of acceleration to maximum speed, to help meet the shortengagement times associated with boost-phase intercepts; and
a kill vehicle different from the Sea-Based Midcourse kill vehicle, because thelatter is designed to operate against a small and relatively cold target, while a boost-defense killvehicle would need to be capable of operating against a large and hot-burningtarget.
The first two characteristics will likely require either a major modification to the existingSM-3 missile design or the development of an entirely new missile with a diameter of up to 27inches. Whether a modified SM-3 or an entirely new design, a higher-speed missile developed forthe Sea-Based Boost program might prove suitable, with a different kill vehicle, for use as animproved interceptor for the Sea-Based Midcourse system. Conversely, a higher-speed missiledeveloped for an improved Sea-Based Midcourse system might prove suitable, with a different killvehicle, for use as the interceptor for the Sea-Based Boost system. (See section on the Sea-BasedMidcourse program.) Using the same basic interceptor missile for both programs could reduce totalsea-based missile defense costs.
It may also be possible, as a near-term stopgap measure, to develop a more limitedboost-phase capability based on the SM-3 missile. Although the SM-3 was designed to interceptslower-moving theater-range ballistic missiles rather than faster-moving intercontinental ballisticmissiles (ICBMs), the SM-3 may have some potential to intercept certain ICBMs -- specifically,those that are fired from coastal launch pads -- during the later (i.e., exoatmospheric) part of theirboost phase, before they have attained their maximum speeds.
A mid-2002 discussion of the sea-based boost concept stated:
Although the radar currently in place on Aegiscombatants has enough power and resolution to detect and track ICBMs during the boost phase, thenavy has optimized the system's performance and displays to defend against targets such as cruisemissiles and missiles launched from airplanes. The required modifications for ICBM defense are nottrivial, but they are achievable. What is totally missing at present is a suitable boost-phase missileinterceptor.
Some U.S. Navy officials proposed using SM-2Block IV (43) missiles toengage boosting ICBMs in the upper atmosphere; that proposal, however, was fraught with a greatdeal of technical risk and required the ship to be within 50 kilometers of the launch site, making theship itself vulnerable. A more practical approach may be developing a missile interceptor intendedto engage the boosting ICBM later in its boost phase above the atmosphere, allowing ships to be asmuch as 1,000 kilometers from the launch site. 
Developers could use the SM-3 test missiles beingproduced for the navy's midcourse risk-reduction effort as a starting point for suitable interceptormissiles. Successful boost-phase intercept missiles, however, would have to be faster than the testmissiles....
Using the modified SM-3 or wide-diameter missiles(fast-accelerating interceptors with high terminal speeds), the ship could be as far as 1,000 kilometersfrom the launch point. U.S. Navy ships thus equipped in international waters could engage missileslaunched from all of North Korea or Iraq. The effectiveness of sea-based boost-phase missile interceptors against ICBMs launched from Iran would depend on the part of the country from whichthe ICBMs were launched. In some cases, U.S. forces would need ground-based or airbornesupplements. 
A sea-based boost-phase capability has clear politicaladvantages and some disadvantages. Its main advantage is the ability to provide a potential defenseagainst ICBMs launched from North Korea and most parts of the Middle East. At the same time, seabasing would present no threat to Russia's and China's land-based ICBM deterrents because thoselaunch points are far inland. 
As for disadvantages, a sea-based boost-phasesystem would potentially threaten Russia's submarine-launched deterrent, assuming a capabilityexisted to estimate the general location of the submarine. Second, any boost-phase defenses wouldrequire the establishment of a "no-launch zone" or other special procedures over the rogue state anda willingness in extremis to delegate the engagement decision to the local U.S. commander. Bothrequirements may be difficult to sustain politically. Finally, any boost-phase concept would requirelaunching the interceptors in the direction of the country launching the ICBMs as well as towardthird parties that may not be involved. For example, launches against North Korean missiles withboost-phase missile interceptors would entail launches on azimuths toward both North Korea andChina. When defending against Iraqi and Iranian missile launches, the boost-phase missileinterceptors would fly over several countries on an azimuth toward Russia. Additionally, debris fromthe engagement (damaged warheads, spent interceptor boosters, and so forth) could have an impacton uninvolved countries. 
If the United States accepts these politicaldisadvantages, the operational advantages of a sea-based boost-phase interceptor are significant.With the potential exception of Iran, these interceptors are most effective against the countries inneed of dissuasion and deterrence, and they are less effective against former adversaries that needreassurance. (44)
MDA Director Kadish stated in July 2001 that the Sea-Based Boost program "is consideringa high-speed, high-acceleration booster coupled with a boost kill vehicle. This same booster willbe evaluated (with a different kill vehicle) for sea-based midcourse roles." (45) The program could bepursued as either a complement to air- and space-based boost-defense systems or a hedge against thepossibility of technical problems in these other programs. General Kadish also stated in July 2001that MDA is "going to institute concept studies and [is] looking at concepts on how to do the boostphase with kinetic energy, as a hedge against the directed energy, should we run into problems there. So we have some experiments in space with the space-based laser, and we're looking at whether weshould be doing some experiments in space with kinetic energy that build on the terrestrial side forairborne laser and a sea-based kinetic energy killer." (46) 
In May 2002 it was reported that
A modified Standard Missile-3 using a newkinetic kill vehicle now being developed by the Missile Defense Agency may be included in a seriesof experiments planned for fiscal year 2004 that will look at promising new approaches to defeatballistic missiles during their boost phase, an MDA spokesman told Inside the Navy last week. MDAplans to spend over $2 billion through FY-07 to develop a boost-phase interceptor that could belaunched from a Navy ship, according to agency budgetdocuments....
MDA spokesman Christopher Taylor told ITNthat during FY-02 the agency and the Navy will develop mission requirements for early criticalexperiments (ECE) scheduled for FY-04. "Current options for the ECE missile include a modifiedStandard Missile-3 that incorporates the new Generation 1 boost kill vehicle under development aswell as other more powerful boosters resulting from MDA's Broad Agency Announcement," hesaid.
The Navy and MDA will also finish a conceptdefinition and assessment study in FY-02 that looks at candidate kinetic energy boost elements ofthe Ballistic Missile Defense System, the layers, multiprogram architecture that will handle a wholerange of ballistic missile threats from ICBMs to the very shortest rangemissiles.
"This study, done in collaboration with theMissile Defense National Team, is assessing a broad range of boost concepts spanning the completeset of basing modes including sea, space, air and ground," Taylor said. "Our intent is to executecritical experiments in FY-03-05 to mitigate the risk in accomplishing the boost mission. Thesecritical experiments may culminate in a focused demonstration of a particular basing modedepending on the results of the CD&A study and the early critical experiments." (47)
In early September 2002, it was reported that the Defense Science Board (a federal advisorycommittee that provides independent advice to the Secretary of Defense) had recommended inAugust 2002 that DOD focus its missile defense efforts on two main approaches: a ground-basedmidcourse system and a sea-based boost and ascent-phase system. (48) 
In June 2002, it was reported that one
boost-phase activity that's materializing involvesmodifying the lightweight exoatmospheric projectile (Leap) used as the kill vehicle in the sea-basedmidcourse defense system. It will gather data on a boosting target, according to Dean T. Gehr,missile defense business development manager for Raytheon. The goal is to conduct a flybyexperiment and determine whether an infrared sensor can detect the missile. Leap's solid-fuel divertand attitude control system (DACS) would likely be replaced with a larger, liquid fuel system thatwould give the kill vehicle more maneuverability.
While the boosting missile is easy to spot because ofits large infrared signature, the weapon becomes encased in a plume of hot gases as it reaches higheraltitude and thinner atmosphere. The seeker then has difficulty finding the missile. Modificationswill likely be made to the IR sensor to look at the bright target, Gehr said. If the IR sensor alone can'tdo the job, it might have to be supplemented with an ultraviolet sensor or laserradar.
For test purposes, the data-collection effort probablywill use the Standard Missile SM-3, which is the interceptor for the sea-based midcourse system.Raytheon hopes a modified SM-3, with a 21-in. second stage, can serve as the interceptor in anoperational configuration, but MDA officials have indicated they may need a dedicated missile.Notional performance for such a system would be 30g acceleration and speeds of 8 km./sec. velocityat burnout. (49)
In October 2002 it was reported that
DOD and industry officials say [MDA] isleaning toward developing a 'multi-use' boost-phase interceptor with a speed of around 6km/s [6 kps]that could be launched from navy ships, but could also be operated from land, even airborne andpotentially have space applications. 
"We have initiated experiments this year todemonstrate the capabilities of a kinetic-energy boost system," said Pat Sanders, program executiveofficer for the MDA's overarching BMDS [Ballistic Missile Defense System]. "We expect toconduct tests to intercept a boosting missile no later than 2005." Later, the same interceptor boostermay be evaluated with a different kill vehicle for mid-course use, DOD officials said. (50)
section_title: Midcourse Defense Segment
paragraphs: [author name scrubbed], Specialist in National Defense 
Ground-Based Midcourse. The Ground-BasedMidcourse Program, also known previously as the National Missile Defense (NMD) program, woulduse some number of ground-based interceptors to seek to defend all 50 states of the United Statesfrom a limited intercontinental-range ballistic missile attack. The kinetic kill warhead on the missilewould seek to destroy its intended target through direct collision during the midcourse phase of theattacking missile or warhead. Major subsystems might include some number of existing and newradars and surveillance platforms, including the Aegis Spy-1 radar, existing early warning radarsand a new X-Band radar, the space-based Defense Support Program, SBIRS (High and Low), andvarious Battle Management, Command, Control, and Communications (BMC 3) components.
Pacific Missile Defense Testbed. The Administrationhas moved forward with the Pacific Missile Defense Testbed (also known as the Midcourse TestBed). The Administration asserts this Test Bed could provide a rudimentary ground-based ICBMdefense contingency capability. 
In December 2002, the Administration announced a specific program and timeline. TheAdministration said the United States would begin fielding initial missile defense capabilities in2004-2005 to meet the near-term ballistic missile threats to the U.S. homeland, to U.S. deployedforces, and to counter ballistic missile threats to U.S. friends and allies. This initial capability wouldbuild on the planned Pacific Missile Defense Testbed and would serve as a starting point fordeploying increasingly effective missile defenses over time, according to the Administration.
The initial set of capabilities in mind for 2004-2005 include 
up to 20 ground-based interceptors designed to intercept and destroy ICBMsduring the midcourse phase of their flight. These interceptors would be based at Ft. Greeley, Alaska(16 interceptors) and Vandenberg Air Force Base, California (fourinterceptors);
up to 20 sea-based interceptors deployed on existing Aegis ships to try andintercept ballistic missiles in the first few minutes after they are launched (i.e., during their boost andascent phases of flight);
deployment of air-transportable PAC-3 systems designed to intercept short andmedium-range ballistic missiles; and
land, sea, and space-based sensors, including existing early warning satellites,an upgraded radar now located at Shemya, Alaska, a new sea-based X-band radar, upgraded existingearly warning radars in the UK and Greenland, and use of other sensors now on Aegis cruisers anddestroyers.
These capabilities could be improved upon through additional measures such as additionalinterceptors of varying capabilities and basing platforms. Ground was broken for the Ft. Greely siteon June 5, 2002, for missile silos and support buildings. The initial ground-based midcourse partsof the testbed are to be constructed by the end of September 2004. The purpose of the test bed is tovalidate the ground-based midcourse concept and to improve the realism of interceptor tests,according to DOD. Other key parts of the testbed are planned or are under construction in Alaska,California, Colorado, the Republic of the Marshall Islands.
Costs. System costs have not been provided. Thesecosts may also not become available because of the evolutionary acquisition strategy adopted formissile defense. Nonetheless, there is a useful point of reference in terms of costing a midcoursesystem. The Clinton Administration considered deploying a system of 100 ground-based interceptorsin Alaska at a cost of about $36 billion (the life-cycle cost was estimated to be about $44.5 billionthrough FY2026). The Initial Operational Capability (IOC) for this system was 2005.
Recent Tests and Technical Challenges. The NMDor ground-based midcourse program has witnessed a number of technical challenges. These includeongoing delays in testing the rocket booster, which in turn has adversely affected decisions onacquiring long-lead interceptor technologies. In addition, modeling and simulation tools that weresupposed to aid the Clinton Administration in its decision whether to deploy a limited NMD inAlaska, were delivered too late to help in that decision. The Integrated Flight Test (IFT) programalso has experienced uncertain results. Although many tests were called successful by the DOD,several post-intercept test analyses have been considered more ambiguous. Much of this debatecenters over the degree to which target missiles or warheads were artificially enhanced to make theintercept more likely. Program delays have occurred regularly. But, a great number of IFT objectiveswere designed to test other aspects of the missile launch, missile flight, and interceptor performance. These other, non-intercept objectives have largely been considered successful.
On December 11, 2002, the Missile Defense Agency announced it could not complete aplanned intercept test because the kill vehicle and the booster rocket failed to separate. This was the8th intercept of the ground-based midcourse research and development program. The first test onOctober 3, 1999, successfully intercepted its intended target. The 2nd test occurred on January 19,2000; an intercept was not achieved because of a problem with the on-board cooling system. The 3rdtest on July 8, 2000, also failed to intercept its target because the kill vehicle failed to separate fromthe booster rocket. The 4th test, on July 14, 2001, successfully intercepted its target, as did the 5th and6th tests on December 3, 2001 and March 15, 2002, respectively. BMDO stated this test is a majorstep in an "aggressive test program," and that it was the "third successful intercept test in fiveattempts." The 7th test on October 14, 2002 was also deemed a success and for the first time aship-based SPY-1 radar was used to track a long-range target.
More recent planned intercept flight tests have been delayed for some time. Currently, theBMD interceptors deployed in Alaska have not been tested in their current configuration (i.e., currentbooster and interceptor). Hence, questions are raised over its performance and effectiveness.
Sea-Based Midcourse. ( [author name scrubbed],Specialist in National Defense )
Ships and SM-3 Interceptor. The Sea-BasedMidcourse program is the successor to the Navy Theater-Wide (NTW) program (which was alsocalled the Navy Upper Tier program). MDA Director Kadish stated in his July 2001 testimony toCongress on the Administration's new missile defense program that "The Sea-Based MidcourseSystem is intended to intercept hostile missiles in the ascent phase of midcourse flight, which whenaccompanied by [the] ground-based system, provides a complete midcourse layer [of defense]. Byengaging missiles in early ascent, sea-based systems also offer the opportunity to reduce the overallBMD System's susceptibility to countermeasures." (51) 
MDA plans to spend about $3.3 billion on the Sea-Based Midcourse program betweenFY2003 and FY2007. Major contractors for the program include Raytheon Missile Systems ofTucson, Arizona (the prime contractor for the development of the interceptor missile), and LockheedMartin Naval Electronic and Surveillance Systems of Moorestown, New Jersey (which manages thedevelopment of the shipboard Aegis Weapon System).
The Sea-Based Midcourse system, like the earlier NTW program, would be based on theNavy's Aegis ships, which are equipped with the powerful SPY-1 radar. (52) The Navy's NTW programwas designed to intercept theater-range ballistic missiles during the midcourse phase of flight, so asto provide theater-wide (i.e., regional) defense of U.S. and friendly forces, vital military and politicalassets ashore, and large geographic areas. Achieving a capability against theater-range ballisticmissiles involves modifying the SPY-1 radar to improve its ability to detect and track ballisticmissiles and developing a new version of the Standard Missile interceptor known as the SM-3. Compared to the earlier SM-2 missile, the SM-3 would incorporate a third-stage rocket motor to givethe missile a higher maximum speed (i.e., a higher "burn-out velocity"), and a kinetic kill vehicle(KKV) called the Lightweight Exo-Atmospheric Projectile (LEAP) that destroys the enemy missileby colliding with it.
MDA Director Kadish's July 2001 testimony and subsequent statements suggest that theAdministration's plan for Sea-Based Midcourse is to proceed with development and deployment ofthe capability envisaged under the NTW program, and then work toward improving the system sothat it can eventually be used against faster-flying intercontinental ballistic missiles (ICBMs). MDAofficials have indicated that if developmental testing goes well, the basic version of the Sea-BasedMidcourse system (the NTW-like version capable of intercepting theater-range ballistic missiles)might be ready for deployment in 2005 or 2006. A more advanced version of the Sea-BasedMidcourse system (a version capable of intercepting ICBMs) might be ready for deployment severalyears after that.
The basic version of the Sea-Based Midcourse system was successfully tested threeconsecutive times in 2002, achieving intercepts on Aries target ballistic missiles on January 25, June13, and November 21. The June intercept occurred on the day that the ABM treaty expired and wasthe first to employ a sea-based Aegis radar to guide the interceptor to the target missile. Both theJanuary and June tests involved descent-phase intercepts. Following the successful result of the Junetest, the flight test program was accelerated with the intention of deploying the system as a near-termdefense against theater-range ballistic missiles in 2005 or 2006. The November test was the first ina series of six flight tests aimed at this goal, and was the first in which the Sea-Based Midcoursesystem intercepted a missile in its ascent phase. The remaining five tests in the series will involvemore complex and stressing engagement scenarios. Three of these five tests are planned for 2003. The first may occur in April or May and the second in August; both are to involve ascent-phaseintercepts. The tests will also explore the potential for the SM-3 to intercept ballistic missiles atlower altitudes in space, so that it can perform part of the mission that was to be performed by thenow-cancelled Navy Area Defense (i.e., Lower Tier) program (see discussion in the Sea-Based Boostsection). (53) 
Improving the Sea-Based Midcourse system so that it can be used against ICBMs wouldlikely involve making additional modifications to the Aegis ships' radars, including furtherimprovements to the SPY-1 radar, which operates in the S band, and the potential addition of a newX-band shipboard radar called the high-power discriminator.
Improving the Sea-Based Midcourse system so that it can be used against ICBMs would alsoinvolve developing a larger and higher-speed missile than the SM-3, which has a maximum speed(i.e., burn-out velocity) of a bit more than 3 kilometers per second (kps). The Navy reportedly hasbeen considering 3 different options for a higher-speed missile: (54) 
Faster SM-3 . This missile, also referred to as the SM-3 Block 1 or theEnhanced NTW missile, would extend the 21-inch diameter of the SM-3's first-stage booster upthrough the second stage, but retain the Standard Missile's original 13.5-inch diameter above thatpoint. It would have a range of 1,000 kilometers and a maximum speed of 4.5 kps, and it wouldcarry an improved version of the NTW missile's LEAP KKV weighing about 30kilograms.
Enhanced SM-3. This missile, also referred to as the SM-3 Block 2 or theImproved 8-Pack missile, would increase the diameter of the Standard missile along its entire lengthto 21 inches -- the maximum diameter that can be fired from the Mk 41 vertical launch system (VLS)installed on Aegis ships. (The Mk 41 VLS is installed on Navy ships in modules that each contain8 missile-launch tubes, leading to the use of the term 8-pack.) This missile would have a range of1,500 kilometers and a maximum speed of 5.5 kps, and it would carry a more capable KKVweighing about 40 kilograms.
New Missile. This missile, also referred to as the Standard Missile 27 or the6-Pack missile, would have a diameter of 27 inches and a longer length than the Standard Missile,and would be fired from a new VLS designed to accommodate missiles of that diameter and length. This new VLS could have 6 missile-launch-tube modules occupying the same deck area as the 8-tubemodules of the current Mk 41 VLS, leading to the use of the term 6-pack. This missile would havea range of more than 1,500 kilometers and a maximum speed of 6.5 kps, and it would carry an evenmore capable KKV, either the same KKV being developed for the land-based NMD system or anadvanced-technology KKV, weighing about 50 kilograms.
In addition to the above missile options, Japan is participating in a cooperative developmentprogram with MDA to develop certain technologies that could be used to improve the SM-3. (55) 
A higher-speed missile developed for an improved Sea-Based Midcourse system might provesuitable, with a different kill vehicle, for use as an interceptor for a Sea-Based Boost system. Conversely, a higher-speed missile developed for the Sea-Based Boost program might provesuitable, with a different kill vehicle, for use as the interceptor for an improved Sea-Based Midcoursesystem. (See section on the Sea-Based Boost program.) Using the same basic interceptor missilefor both programs could reduce total sea-based missile defense costs.
Sea-Based X-Band Radar. Independent of theAegis-ship program described above, MDA announced on August 1, 2002 that it wants to build alarge, sea-based, X-band missile tracking and engagement radar to support the Ground-BasedMidcourse system. This sea-based radar would be built in lieu of a ground-based X-band missiledefense radar. MDA wants the sea-based radar to be deployed by September 2005 as part of thePacific missile defense development test bed. The sea-based radar option was selected over thealternative of building an additional ground-based X-band radar in large part because the ability toreposition a sea-based radar permits the creation of a numerous radar configurations that can supporta variety of missile-defense development tests and emerging missile defense requirements. Boeingand Raytheon are main contractors for the radar, whose total acquisition has been estimated at about$900 million. (56) Nofunds specifically for the sea-based X-band radar were included in the FY2003 defense budgerequest.
Under MDA's plans, the X-band radar is to be carried aboard "a modified, fifth generationsemi-submersible platform similar to those currently used in the oil exploration industry." Theplatform would have a length of 390 feet, a beam (width) of 238 feet, and a draft of 77 feet. It woulddisplace 50,000 tons, which is about half the full load displacement of a U.S. Navy Nimitz-classaircraft carrier. It would have a deck area measuring 270 feet by 230 feet and would be able torelocate itself using electric thrusters. The X-band radar would sit on the deck, encased in aspherical shell. (57) Thegeneral concept of deploying large radars on sea-based platforms is not new: The United States overthe years has outfitted and operated several merchant-type ships with large radars similar to MDA'sproposed X-band radar to support flight tests of U.S. ballistic missiles and reportedly to learn aboutthe characteristics of foreign ballistic missiles.
section_title: Terminal Defense Segment
paragraphs: Ground-Based Terminal. ( [author name scrubbed],Specialist in National Defense) 
Patriot PAC-3. The Patriot PAC-3 (PatriotAdvanced Capability-3, MIM-104 Patriot/ERINT) is the U.S. Army's primary medium-range airdefense missile system and is considered a major system improvement over the Patriot used in theGulf War, and of the subsequent PAC-2. It will target enemy short- and medium-range missiles intheir mid-course or descent phase in the lower atmosphere, and will be used in conjunction with thelonger-range THAAD. When all changes have been made, the PAC-3 will have a new hit-to-killinterceptor missile (the ERINT), improved communications, radar, and ground support systems. Thefirst unit to be equipped with the final version is receive PAC-3 missiles in late 2001 at Fort Bliss,Texas. Full-rate production was scheduled to begin in late 2001, but slipped to late 2002.
In April 2000, the Pentagon projected costs of PAC-3 had increased by $102 million to $2.9billion because of increased reliability and spares costs. A GAO report issued in July 2000 showedPAC-3 total program costs increased from $3.9 billion for 1,200 missiles planned in 1994 to $6.9billion for about 1,012 missiles in the current plan. In April 2001, BMDO estimated the PAC-3acquisition costs to be $10.1 billion. BMDO and the Army are attempting to cut the current cost ofthe missile to allow the purchase of additional missiles. In December 2000, the Army announcedit had restructured the program to finish testing and begin full-rate production earlier. It also plansto increase the numbers purchased in the years 2003-2007. For FY2002, the Bush Administrationrequested $784 million for PAC-3, a 76% increase over the amounts requested and approved forFY2001. The Administration also transferred funding for the PAC-3 from BMDO to the Army. TheHouse Armed Services Committee, in its version of the FY2002 Defense Authorization Bill did notapprove this transfer; this too was later sustained in Congress. 
Beginning in 1999, PAC-3 had a successful string of intercept flight tests destroying 10 of11 targets, prior to a partial test failure in February 2002 (one PAC-2 missile intercepted a droneaircraft, while a second PAC-2 and a PAC-3 missile missed their intended targets). Subsequentsuccessful intercepts occurred on March 21, April 25, and May 30, 2002.
A concern raised was the rising costs of PAC-3. It has been argued that unit costs could bereduced by increasing the number of units purchased and increasing the pace of production. If morecountries buy PAC-3, and if the MEADS program is fielded with PAC-3 missiles, unit costs wouldbe further reduced. (Germany, the Netherlands, Japan, Israel, and Taiwan have Patriot systems andare in various stages of upgrading them. South Korea is considering buying Patriots and Germanyand Italy are participating in MEADS, which would use Patriot missiles.)
In May 2000, DOD decided to stop development of PACM (designed to defeat cruisemissiles) because PAC-3 and improvements being made to PAC-2 systems provide a more costeffective defense against ballistic and cruise missile threats. The decision has been controversial,particularly among companies that would have produced PACM. But the conference report on theFY2001 authorization bill noted no funds had been requested for PACM and instructed the Secretaryof Defense to determine if PACM production is warranted.
The effectiveness of PAC-3, and other missile defenses, against countermeasures is also anissue. Russia has developed a guided warhead for the Scud missile that it claims has an accuracyof 10-20 meters, can defeat Patriot missile defenses, and is immune to jamming and electroniccountermeasures. It was reported in March 2001 that Russia is offering this warhead for sale to anumber of countries in the Middle East that have Scud missiles.
Theater High Altitude Area Defense (THAAD). TheTHAAD program is the U.S. Army's weapon system designed to destroy non-strategic ballisticmissiles just before they reenter the atmosphere or in the upper atmosphere. The THAAD missilewould use a single-stage, solid propellant rocket and a hit-to-kill interceptor designed to destroy theattacking missile with the kinetic energy of impact. Unlike lower-tier, shorter range systems, suchas the Patriot PAC-3 and MEADS, THAAD is intended to help protect wider areas against missilesand falling debris of missiles, as well as possible nuclear, biological, or chemical materials.
In April 2000, the Pentagon released a Selected Acquisition Report stating the projected costsof THAAD had increased by $898 million to a total of $9.5 billion because of a revised estimatingmethodology. In April 2001, BMDO estimated THAAD acquisition costs to be $16.8 billion, andthe life cycle costs to be $23 billion.
THAAD entered the Engineering and Manufacturing Development (EMD) phase in late June2000. A more advanced version designed to defeat attacking missiles employing countermeasureswas scheduled for 2011. In an accelerated development proposal the Army considered in 2000, thefirst THAAD unit equipped could be moved from FY2007 to FY2006. The Department of Defenseis still studying this accelerated option. Simultaneously, DOD is relaxing the requirement thatTHAAD be able to intercept targets within and outside the atmosphere, raising the altitude at whichit must be able to conduct an intercept. The minimum intercept altitude had been 40 kilometers.
Earlier technological problems in THAAD's development jeopardized support for the system. But on June 10, 1999, after THAAD had failed in six previous interceptor flight tests, the firstsuccess was achieved. In each of those six previous unsuccessful intercept flight tests, a differentsubsystem had failed. On August 2, 1999, a second THAAD missile successfully intercepted a targetmissile.
After the second successful intercept, Lockheed Martin submitted a proposal for movingTHAAD in EMD, but the Army Space and Missile Defense Command rejected the proposal in April2000 because of management and testing plan deficiencies. Lockheed Martin addressed theseproblems, and the Army later recommended the Defense Acquisition Board (DAB) begin its reviewof THAAD advancing to EMD.
Because of concerns that the THAAD and NTW programs were not being tested againsttarget missiles with the speed and other characteristics of likely enemy missiles (such as the NorthKorean Taep'o-dong 1), Representative Vitter introduced legislation in 1999 (H.R. 2596)that would have required BMDO to make appropriate program management and technologyadjustments in the NTW and THAAD programs. Similar legislation in the 107th Congress, such as H.R. 1282 , was designed to help NTW and THAAD improve their likelihood ofsuccessful intercepts against more realistic test targets.
For FY2002, the Bush Administration requested $922 million for THAAD, which was a 68%increase over the amount requested and appropriated for FY2001 ($549.9 million), and a 32%increase over the amount requested for FY2002 by the outgoing Clinton Administration. Congresscut THAAD funding by $50 million for FY2002. This cut was directed at denying theAdministration's request to acquire a limited number of THAAD contingency missiles. The FY2003request for THAAD is $935 million.
Medium Extended Air Defense System (MEADS). The Medium Extended Air Defense System (MEADS), is a multinational, ground-based, mobile,air and missile defense system. It is essentially a composite of existing technologies with eithersimilar or enhanced capabilities. It will cover the lower-tier of the layered air and theater missiledefense and will operate in the division area of the battlefield to protect against various airbornethreats. Distinguishing characteristics of MEADS are its stated ability to maneuver and deployquickly and to provide 360-degree coverage. It will be able to accompany troops within the theaterand will require less manpower and logistical support to operate than other missile defense systems. MEADS will use the Patriot PAC-3 missile with its hit-to-kill warhead, designed to interceptmultiple and simultaneous short range ballistic missiles (SRBMs), low cross-section cruise missilesand aircraft, and unmanned aerial vehicles. MEADS will eventually replace the aging HAWK airdefense system. In addition to fulfilling operational requirements for limited air defense, theprogram is also expected to reinforce interoperability of NATO forces and to reduce the U.S. burdenof cost for helping to maintain European defense. 
BMDO has been responsible for program direction and system architecture and integration. The Pentagon sought to shift the management of MEADS and PAC-3 to the Army from BMDO. Some question whether the Army will give the program sufficient budget priority to sustaindevelopment. The House Armed Services Committee did not approve this transfer in its version ofthe FY2002 Defense Authorization Bill, and this was upheld by Congress.
Under the initial May 1996 Memorandum of Understanding, Germany and Italy committedto fund 25 percent and 15 percent of the program, respectively, for the next 10 years. The Germanmilitary has questioned the number of MEADS units it would need and whether it could afford them,the German Parliament balked at approving its share of development costs, and the Germangovernment then asked to have the program restructured to reduce its $22 billion cost, even if thatrequired reduced capability. In July 2001, the NATO MEADS Management Agency granted athree-year, $216 million risk reduction contract to MEADS International (a team consisting ofLockheed Martin, Alenia Marconi, and the European Aeronautic Defence and Space Company). The United States will pay 55 percent of the risk reduction program, Germany 28 percent, and Italy17 percent. The agreement was modified to divide German funding and commitment into threephases to ease the Defense Ministry's negotiations with Parliament. Germany has also decided tostop upgrading its Patriot batteries until it can determine whether MEADS will duplicate Patriot'scapabilities. The definition phase of development has been extended three years thus puttingdeployment off till 2009.
Responding to congressional criticism of the program's costs for FY2001, Pentagon officialssuggested that Germany and Italy coproduce the Patriot PAC-3 interceptor for incorporation intoMEADS. In April 2000 it was reported that Germany and Italy had tentatively agreed touse the Patriot rather than a new interceptor, but still plan to develop a new seeker radar.
For FY2002, the Administration requested $74 million for development of MEADS, $20million more than was appropriated for FY2001 (the defense authorization act for FY2001decreasedthe requested amount by $9.7 million.) In the final appropriations bill, funding for MEADS was cutslightly.
The Lockheed-Martin Corp. and the Hughes Aircraft and Raytheon Company consortiumrepresented the U.S. partners of two competing international teams. Alenia of Italy, and EuropeanAeronautic Defence and Space Company (formerly Daimler-Chrysler Aerospace) of Germany,represent the European group. In May 1999, the three governments selected the team headed byLockheed Martin to develop MEADS. Target production and fielding dates were set for 2006 but have slipped to 2009.
In May 1996, France rescinded its initial commitment to fund 20 percent of the MEADSprogram. Despite budgetary constraints, however, France is still interested in developing missiledefenses, perhaps an indigenous system. The United Kingdom is not a participant in the programand to date has taken no official position on it. The Netherlands and Turkey have also consideredparticipating in the joint endeavor.
Sea-Based Terminal. ( [author name scrubbed],Specialist in National Defense )The sea-based terminal effort has undergone a number of recentchanges. These are described below.
Cancellation of NAD Program. On December 14,2001, DOD announced that it had canceled the Navy Area Defense (NAD) program, the programthat was being pursued as the Sea-Based Terminal portion of the Administration's overallmissile-defense effort. In announcing its decision, DOD cited poor performance, significant costoverruns, and substantial development delays. (58) DOD stated that the program's unit acquisition and unitprocurement costs had risen 57 percent and 65 percent, respectively. (59) 
In announcing the cancellation, DOD cited the Nunn-McCurdy provision, a defenseacquisition law passed in the 1980s. Under the law, a major defense acquisition programexperiences what is called a Nunn-McCurdy unit cost breach when its projected unit cost increasesby at least 15 percent. If the increase reaches 25 percent, the Secretary of Defense, to permit theprogram to continue, must certify that the program is essential to national security, that there are noalternatives to the program that would provide equal or greater military capability at less cost, thatnew estimates of the program's unit acquisition cost or unit procurement cost appear reasonable, andthat the management structure for the program is adequate to control the program's unit acquisitionor unit procurement cost.
Edward C. "Pete" Aldridge, the Under Secretary of Defense for Acquisition, Technology andLogistics -- the Pentagon's chief acquisition executive -- concluded, after examining the NADprogram, that he could not recommend to Secretary of Defense Donald Rumsfeld that he make sucha certification. Rumsfeld accepted Aldridge's recommendation and declined to issue thecertification, triggering the program's cancellation. This was the first defense acquisition programthat DOD officials could recall having been canceled as a result of a decision to not certify under aNunn-McCurdy unit cost breach. (60) 
DOD stated that the cancellation of the program would "result in a work stoppage at somegovernment and contractor facilities." Major contractors for the NAD program were Raytheon ofTucson, AZ, Lockheed Martin of Moorestown, N.J. and Middle River, MD, United Defense ofBaltimore, MD, and Minneapolis, MN, Orbital Sciences of Dulles, VA and Chandler, AZ, and L-3Communications of New York, NY. Major government field activities involved in the program werethe Naval Surface Warfare Center (NSWC) at Dahlgren, VA, NSWC at Port Hueneme, CA, theApplied Physics Laboratory of Johns Hopkins University of Laurel, MD, and Lincoln Laboratoriesof the Massachusetts Institute of Technology of Lexington, MA.
Regarding termination costs for the NAD program, it was reported in early November 2002that
The Defense Department has granted Raytheona three-month extension for submitting a formal proposal for termination costs tied to one of twocontracts the company held under the canceled Navy Area missile defense program, according to acompany spokeswoman and a DOD official....
At the time of the cancellation, Raytheon heldtwo contracts -- one for low-rate initial production [LRIP] and one for the engineering andmanufacturing development [EMD] phase of the program. Under federal acquisition regulations, acontractor has one year from contract termination to submit a final termination proposal, the DODofficial said. Raytheon was formally notified of the Area program's contract termination in January2002 and the final settlement proposal would normally be received by January 2003, hesaid.
But Raytheon asked for the extension on theEMD contract "due to the large number of complex subcontracts associated with vendor parts onStandard Missile-2 Blk IVA," Raytheon spokeswoman Sara Hammond told Inside the Navy lastweek. The SM-2 Blk IVA missile carried the interceptor warhead the Navy was going to use for theArea program.
"As such, Raytheon expects to submit the LRIPproposal in January and the EMD contract in April 2003," Hammond said. The DOD official saidthat after the department receives Raytheon's final proposal, there would "be a period of negotiation,normally several months, until final settlement is reached."
At the time of the cancellation, sister publicationInside Missile Defense reported the Navy had estimated termination costs for Raytheon to be slightlymore than $200 million. That breaks down to $106.9 million for the EMD contract and $95.3 millionfor the LRIP contract, according to the Navy figures. Both of those contracts were tied to the SM-2Blk IVA development. (61)
Post-Cancellation Strategy. Following cancellationof the program, DOD officials stated that the requirement for a sea-based terminal system remainedintact. This led some observers to believe that a replacement sea-based terminal defense programmight be initiated. In May 2002, DOD announced that instead of starting a replacement program,MDA had instead decided on a two-part strategy to (1) modify the SM-3 missile to be used in thesea-based midcourse program to intercept ballistic missiles at lower altitude, and (2) modify theSM-2 Block 4 air defense missile (i.e., a missile designed to shoot down aircraft and cruise missiles)to cover some of the remaining portion of the sea-based terminal defense requirement. DODofficials said the two modified missiles could together provide much of the capability that was tohave been provided by the NAD program. One aim of the modification strategy, DOD officialssuggested, was to avoid the added costs to the missile defense program of starting a replacementsea-based terminal defense program. (62) 
In June 2002, it was reported that engineers are "grappling with" the issue of
how to adapt the SM-3 to attack shorter range(100-300-km.) targets. Since the demise of the Navy Area Wide project that was designed forScud-like targets, the Pentagon has looked for solutions to bridge the gap. One option is to haveSM-3 take on part of the mission. To engage targets at shorter ranges, SM-3 would be modified sothe missile has the flexibility not to fire its two-pulse third stage, or fire just the first of two pulses.The goal is to be able to intercept the target near its apogee, outside the atmosphere where Leap (63) operates.
The Navy's Standard defense missile, the SM-2Block 4, is viewed as another stopgap system, particularly for intercepting targets within theatmosphere. Testing will concentrate on three configurations -- unmodified, software modificationsto both the Aegis radar system and missile, and hardware and software changes.
Software adjustments being considered includeadapting some of the [NAD] missile's autopilot and fuze modes to the SM-2 Block 4. The [NAD]interceptor, SM-2 Block 4A, had a high degree of commonality with the Block 4 air defenseweapon. (64)
In October 2002, it was reported that
Upon cancellation of the Navy Area program,the MDA commissioned industry and government teams to study successor options to the SM-2 BlkIVA. The teams found the most promising to be a modified Patriot Advanced Capability-3 missilewith a booster and a program to modify the SM-2 Blk IV - which lacks the infra-red sensor of the[NAD program's] IVA model - to give it terminal BMD capabilities. Both options were envisagedas hit-to-kill systems, unlike the SM-2 family, which has blast-fragmentation warheads. Earlier thisyear the MDA said it intended to pursue the SM-2 Blk IV route and conduct tests to assess its abilityto defeat short-range ballistic missiles "as high in the endo-atmosphere as possible through acombination of software and hardware modifications"....
Senior navy officials... continue to speak of theneed for a sea-based terminal BMD capability "sooner rather than later" and have proposed a pathto get there. "The cancellation of the Navy Area missile defence program left a huge hole in ourdeveloping basket of missile-defence capabilities," said Adm. [Michael] Mullen. "Cancelling theprogram didn't eliminate the warfighting requirement. "The nation, not just the navy, needs asea-based area missile defence capability, not to protect our ships as much as to protect our forcesashore, airports and seaports of debarkation" and critical overseas infrastructure including protectionof friends and allies. 
The service intends to begin funding anext-generation anti-air warfare (AAW) interceptor in FY04, which it calls the 'Extended-RangeActive Missile', to fill the air-defence gap left by the termination of the [NAD program's] SM-2 BlkIVA. It will have a range approaching 200nm.... Unlike the dual-mission SM-2 Blk IVA, the newmissile will be configured solely for AAW. The navy, however, wants the design to allow for theeasy evolution to a separate terminal-phase BMD variant. "Our hope is that we will create a productthere, that while fulfilling our air-defence needs, makes it an option for them [the MDA] to leverageif they choose to do it," said Adm [Philip] Balisle. "They will have to make that decision in thecontext of the contribution to the [BMD] family of systems." (65)
section_title: Sensors Segment
paragraphs: [author name scrubbed], Specialist in Aerospace & Telecommunications Policy 
The sensors program element includes funding for the Space-Based Infrared System-Low(SBIRS-Low); the Russian-American Observation Satellite, or RAMOS (an international cooperativeproject to develop new missile early warning sensor technology); and program operations. ForFY2003, the request was $294 million for SBIRS-Low, $69 million for RAMOS, and $10 millionfor program operations, a total of $373 million. In the FY2003 DOD appropriations andauthorization acts, Congress approved the full $294 million for SBIRS-Low and the $10 million foroperations. Regarding RAMOS, the authorization act cut the request by $10 million, and theappropriations act cut it by $26 million, although it also added $7 million for RAMOS solar arrays.
Of these projects, SBIRS-Low is the most visible and controversial. It is one component ofthe Space Based InfraRed System (SBIRS), which is designed to replace and enhance the capabilitiesof existing satellites that provide early warning of missile launches. Historically, U.S. early warningsatellites have been placed in geostationary orbit, high above the equator (22,300 miles). SBIRS alsowill use satellites in that orbit, as well in highly elliptical orbits, and in low orbits. Hence, the SBIRSprogram is divided into two components: SBIRS-High and SBIRS-Low. For more on bothSBIRS-High and SBIRS-Low, see CRS Report RS21148 , Military Space Programs: IssuesConcerning DOD's SBIRS and STSS Programs , by [author name scrubbed]. SBIRS-High is managed bythe Air Force and will not be discussed further here. Management of SBIRS-Low was moved fromthe Air Force to the Ballistic Missile Defense Office (now the Missile Defense Agency) effectiveOctober 1, 2001, to emphasize that its primary objective is to support missile defense. 
The mission of SBIRS-Low (66) is to track missiles from launch to intercept or reentry; discriminate between targets and decoys; transmit data to boost, midcourse and terminal defensesystems that will cue radars and provide intercept handovers; and provide data for intercept hit/killassessments. 
Because of deep concerns about the technological readiness of SBIRS-Low, and escalatingcost projections, Congress appropriated no funding for SBIRS-Low in FY2002 ($385 million hadbeen requested). However, it appropriated $250 million for "Satellite Sensor Technology" and gavethe Secretary of Defense discretion as to whether the funding should be spent on SBIRS-Low orother technologies. The decision was to continue with a restructured SBIRS-Low program. 
On April 15, MDA Director General Ronald Kadish submitted the restructuring plan toCongress. The SBIRS-Low design last year envisioned a system consisting of between 20 and 30satellites in low Earth orbit (the exact number had not been finalized). The first launch wasprojected for 2006. FY2003 DOD budget materials indicated that the launch would slip to 2008,but under the April 15 restructuring plan, two demonstration satellites will be launched beginningin FY2006 or FY2007. MDA is using its "spiral development" strategy for SBIRS-Low and thesetwo research and development (R&D) satellites will have less capability than what was ultimatelyenvisioned. In the late 1990s, DOD planned to launch three demonstration satellites, called theFlight Demonstration System (FDS), but terminated that effort in 1999 due to rising costs. Now,DOD is returning to the demonstration satellite approach. Sensors and flight structures built for theFDS satellites will be used for the R&D satellites identified in the restructuring plan. According tothat plan, new technologies will be introduced as they mature, with incremental improvements insatellite lifetimes, focal plane arrays, and cryocoolers, for example.
Because the program recently was restructured, and there is no final system architecture, costestimates are problematic. The General Accounting Office (GAO) reported (67) in February 2001 thatDOD, using the system description at the time, estimated that the life-cycle cost for SBIRS-Lowthrough FY2022 was $11.8 billion. A January 2002 Congressional Budget Office (CBO) report (68) estimated the cost through2015 at $14-17 billion (of which $1 billion was appropriated prior to FY2002). In its report on theFY2002 DOD appropriations bill, the House Appropriations Committee reported ( H.Rept. 107-298 ,p. 250) that the program's life cycle cost had grown from $10 billion to over $23 billion. The April15 restructuring plan did not include a new DOD cost estimate, but said that out-year fundingestimates would be developed as part of the FY2004-2009 FYDP.
Two industry teams were chosen in 1999 for program definition and risk reduction (PDRR).The Spectrum Astro/Northrop Grumman team included Boeing, Lockheed Martin, and others. TheTRW/Raytheon team included Aerojet, Motorola, and others. DOD had been expected to select oneof the teams for the next phase (EMD) in mid-2002. However, as part of the April 15 restructuringplan, DOD decided to merge the two teams. TRW was named the prime contractor, and SpectrumAstro a major subcontractor, for the satellites. Competition at the sensor subcontractor level willcontinue, though. with Raytheon and Northrop Grumman pursuing independent parallel sensordevelopment to demonstrate on-orbit performance with the series of R&D satellites.
The February 2001 GAO report raised questions over whether SBIRS-Low could meet itstechnical milestones. GAO concluded that five of six critical satellite technologies were tooimmature to ensure they would be ready when needed: the scanning infrared sensor, tracking infraredsensor, fore optics cryocooler, tracking infrared sensor cryocooler, and satellite communicationscrosslinks. GAO also cited concurrency as a concern in that satellite development and productionwere scheduled to occur at the same time; the results of an on-orbit test would not be available untilfive years after the satellites entered production; and software would be developed concurrent withthe deployment of the satellites and not be completed until more than three years after the firstSBIRS-Low satellites were launched. Other critics cite the ability to discriminate between targetsand decoys, and the ability to share information between satellites, as significant technicalhurdles. (69) 
section_title: Recent Congressional Action
paragraphs: [author name scrubbed], Specialist in National Defense
subsections: section_title: FY2006
paragraphs: For FY2006, the Bush Administration requested $8.73 billion for the Missile DefenseAgency. 
On May 25, 2005, the House approved its version of the defense authorization bill( H.R. 1815 ). The House bill includes $8.83 billion for MDA (an increase of $100million for additional testing of the ground-based missile defense system being deployed). TheSenate Armed Services Committee marked up its version of the authorization bill ( S. 1042 ) on May 12, 2005, to include $8.73 billion for MDA. The Committee also specified that $100million of the funds added to the Mid-Course Segment should be used to enhance the missile defensetest program. The Senate approved its version of the defense authorization bill (S. 1042)on November 14, 2005. The bill specifies an additional $100 million to enhance the GMD testprogram. 
On June 20, 2005, the House approved its version of the defense appropriations bill( H.R. 2863 ). The bill includes $8.58 billion for MDA, adding $100 million foradditional GMD testing and $82 million to develop a multiple kill vehicle. The Senate passed thedefense appropriations bill on October 6, 2005. It included $200 million for additional GMD testingand $65 million for the Israeli Arrow system.
section_title: FY2005
paragraphs: For FY2005, the Bush Administration requested $10.2 billion for all missile programs. Thisincluded about $9.17 billion for MDA and about $1.02 billion for other DOD missile defenseprograms, primarily in the Army (e.g., PAC-3 and MEADS).
On July 22, 2004, the House and Senate approved a conference agreement that provides $10billion ($9.995) for all missile defense programs. This was signed into law ( P.L. 108-287 ) onAugust 5, 2004. More recently, the FY2005 defense authorization bill provided $9.95 billion forBMD programs. This was signed into law on October 28, 2004.
section_title: FY2004
paragraphs: On February 3, 2003, the Department of Defense announced that the Administration wouldask Congress for $9.1 billion for missile defense spending for FY2004, and $9.7 billion for FY2005. 
House and Senate conferees approved the defense appropriations bill on September 24, 2003.The bill was then passed in the House on that date, and in the Senate the following day. The FY2004defense appropriations act ( P.L. 108-87 / H.Rept. 108-283 ) was signed into law on September 30,2003. The bill provided $9.1 billion for missile defense programs. 
section_title: FY2003
paragraphs: In early February 2002, Defense Secretary Rumsfeld announced that the Administrationwould ask for $7.8 billion for missile defense spending for FY2003. However, when the MDAprovided Congress details of its budget, the amount requested was considerably less ($6.7 billion). The Pentagon then attempted, as it had the previous year, to remove the PAC-3 program and fundingfor it from the MDA to the Army. The total amount for Patriot (PAC-3 EMD, modifications,procurement and spares) is $859 million. MEADS was an additional $118 million, bringing thecombined total request for missile defense spending for FY2003 to about $7.68 billion. House andSenate conferees reached agreement on October 9, 2002, and approved $7.6 billion for missiledefense programs ( H.R. 5010 ).