the science (and politics) of missile...

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The Science (and Politics) of Missile Defense Steve Fetter University of Maryland, College Park Philosophical Society of Washington 9 November 2001

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The Science (and Politics) ofMissile Defense

Steve FetterUniversity of Maryland, College Park

Philosophical Society of Washington9 November 2001

Outline

• A brief history of missile defense• A description of the proposed National

Missile Defense (NMD) system• The vulnerability of this type of system

to countermeasures• Other missile defense concepts• Politics of missile defense

A Brief History: 1950s-1972Nike → Sentinel → Safeguard

Sprint and Spartan interceptors5-megaton Spartan warhead

PAR Phased Array Radar

A Brief History: 1950s-1972Nike → Sentinel → Safeguard

ABM Treaty of 1972

The US and the USSR…Considering that effectivemeasures to limit ABM systems would be asubstantial factor in curbing the race in strategicoffensive arms…Have agreed:

Article IEach Party undertakes not to deploy ABM systemsfor a defense of the territory of its country andnot to provide a base for such a defense, and notto deploy ABM systems for defense of anindividual region except as provided for in ArticleIII of this Treaty.

A Brief History

1983 Reagan “star wars” speech, SDI born1991 End of the Cold War

Gulf War, Iraqi Scud attacks1993 SDIO → BMDO, focus shifts to theater

defense1995 Contract for America: NMD by 20031996 Clinton NMD plan; talks with Russia begin1998 Rumsfeld Report

Taepo-dong launch by North Korea2001 Bush: withdraw from ABMT, deploy NMD

National Missile Defense Act of 1999

It is the policy of the United States to deploy assoon as is technologically possible an effectiveNational Missile Defense system capable ofdefending the territory of the United States againstlimited ballistic missile attack (whether accidental,unauthorized, or deliberate)…

It is the policy of the United States to seekcontinued negotiated reductions in Russiannuclear forces.

Proposed NMD System Concept

Proposed NMD System Components

Satellites in high orbits detect the hotplume of the enemy missile, cue radars

Satellites in low orbits use LWIR totrack warheads in space

Radars track incoming warheads

Upgraded Early Warning Radar

X-Band Radar

Ground-basedInterceptor (GBI)is launched

Kill vehicle uses LWIR to home on thewarhead, destroying it by colliding with it:

“hit-to-kill intercept”

Clinton plan: start small, add additionalinterceptors, sensors, sites over time

$49*$36*$30Cost (billion)201120102005-07IOC

DSP → SBIRS-highFB-XBR, SBIRS-lowUEWR

XBR at GBI sitesOthersensors

125 GFAlaska125 AK10020-100

GBIs

larger attackwith better

CM

small attackw/CM

small (5 RV)attack, no CM

Intendedcapability

C3C2C1

*Does not include $11 billion for SBIRS-low

Hit-to-kill intercept has proved difficult:• Of 22 tests of exoatmospheric hit-to-kill systems

(4 HOE, 2 ERIS, 4 LEAP, 8 THAAD, 4 NMD),only 6 have scored a “hit”

• Recent problems often related to quality control;BMDO criticized for “rush to failure”

• Tests unrealistic (no decoys or one balloondecoy, one-on-one engagements in one head-on,short-range geometry), using “surrogates”(beacon/GPS, low-acceleration booster)

Nevertheless, reliable hit-to-kill interceptshould be possible in test situations

The proposed NMD system—and anysimilar system—is unlikely to workagainst a real adversaryA country or group able to build (or buy) an ICBM,RV, and nuclear or biological warhead, would alsobe able to build (or buy) effective countermeasuresto an exoatmospheric hit-to-kill system

“However absorbed a commander may be in theelaboration of his own thoughts, it is sometimesnecessary to take the enemy into account.”

—Winston Churchill

Countermeasures

A Technical Evaluation of theOperational Effectiveness of the Planned

US National Missile Defense System

Andrew M. Sessler (Chair), John M. Cornwall, Bob Dietz, Steve Fetter,Sherman Frankel, Richard L. Garwin, Kurt Gottfried, Lisbeth

Gronlund, George N. Lewis, Theodore A. Postol, David C. Wright

Union of Concerned ScientistsMIT Security Studies Program

April 2000

Available at http://www.ucsusa.org

Three countermeasures examined in detail:• biological submunitions• nuclear warhead with antisimulation balloons• nuclear warhead with cooled shroud

Each countermeasure• defeats midcourse hit-to-kill systems (NMD,

THAAD, NTW)• can be deployed by new missile state, without

flight testing

Biological Submunitions

• submunitions or “bomblets” are the preferredmethod of delivering CBW agents– better coverage of target– better dispersal efficiency

• 100 bomblets/missile, 2 kg anthrax/bomblet,could result in ~100,000 deaths

• dispense bomblets soon after boost phase ends,before interceptors can reach payload

• design of dispensing mechanism, submunitionsstraightforward

Antisimulation Balloon Decoys

• Instead of making decoys look like warheads,make the warhead look like a decoy

• Enclose warhead in a mylar balloon; alsorelease many empty balloons (1 lb each)

• Trajectories, radar/IR signatures almost identical• Empty balloons could display diversity of

signatures (size, shape, temp, mass, spin)• Even a “hit” may not destroy warhead inside• Implementation not difficult

Cooled Shroud

• Place nuclear warhead in a shroud cooled withliquid nitrogen

• Million-fold reduction in IR signal (at 10 µm)– Thousand-fold reduction in detection range– Warhead is detected too late for homing

• Current KV does not use visible light for homing,but night launch (or polished surfaces) wouldprevent this

• Implementation not difficult (~100 kg extra mass)

Countermeasures Video

Other NMD ConceptsImproved midcourse defense• Improved discrimination

– radars to monitor dispensing of warhead, decoys– lasers to “push” balloons

• Destroy everything– Nuclear-armed interceptors– Multiple miniature kill vehicles

Terminal defense• Atmosphere strips away decoys, but too many

targets to defend

Boost-phase DefenseMany advantages:• destroy entire payload• booster easier to detect, track, and destroy• defended area much largerKey disadvantage:• Must be close to launch point, at launch time

– space-based systems in orbit– land, sea, or air-based systems near enemies

• could not intercept missiles launched deep insideRussia or China

0 100 200 300 400 500 600 7000

100

200

300

400

500

600

700

Range (km)

Altitude (km)

200

0 100 200 300 400 500 600 7000

100

200

300

400

500

600

700Missile Powered Flight Profile

Range (km)

Altitude (km)

A

ltitu

de (k

m)

Alti

tude

(km

) Flight profiles of GBI and Navy Theater-Wide Interceptor

Flight profiles of typical and fast-burning ICBMs

Locations shown at 5second intervals

70 s8.5 km/s

55 s5.5 km/s

130 s

250 s 320 s

0 100 200 300 400 500 600 7000

100

200

300

400

500

600

700

Range (km)

Altitude (km)

Boost-phase Engagement

Intercept point if interceptorlaunched 95 s after ICBM

Location of ICBMwhen interceptoris launched

GBI at 100 s

ICBM at250 s

GBI at 150 s

North Korean missile attacks on Moscow,Washington, Chicago, San Francisco, and Honolulu

North Korean missile attacks on Moscow,Washington, Chicago, San Francisco, and Honolulu

Vladivostok

Moscow Washington Chicago San Francisco

Honolulu

Boost-phase Engagement

Honolulu

Washington DC Chicago San Francisco

Honolulu

Range of GBI 150 Seconds After Launch

End of North Korean ICBM Powered Flight

Intercept Points If GBI is Launched 50 Seconds After ICBM is Launched

Moscow

Last Chance Intercept If GBI Launched 125 Seconds After ICBM Launch

Intercept Points If GBI is Launched 100 Seconds After ICBM is Launched

Range of GBI 125 Seconds After Launch

Range of GBI 190 Seconds After Launch

Range of GBI 100 Seconds After Launch

Interceptor Burnout Speed ! 8.5 km/se c

Boost-phase Engagement

Honolulu Washington DC San Francisco

Honolulu

Range of Boost -Phase GBI 190 Seconds After Launch Range If Interceptor Launched Within 60 Seconds of ICBM Launch

ICBM Launch

Point

Interceptor Burnout Speed ≈ 8.5 km/sec

Boost-phase Engagement

Honolulu Washington DC San Francisco

Honolulu

Range of Boost -Phase GBI 190 Seconds After Launch Range If Interceptor Launched Within 60 Seconds of ICBM Launch

ICBM Launch

Point

Interceptor Burnout Speed ≈ 8.5 km/sec

Other Modes of Delivery

• ICBMs are not the only (or even the best) wayto deliver nuclear or biological weapons:– short-range ballistic missiles or cruise missiles

launched off ships– airplanes– covert delivery (e.g., shipping container on

commercial ship)• Third-world ICBMs are less reliable and more

effective than other modes of delivery• Unlike missiles, no “return address”

International Politics of NMD

Russia and China worry about U.S. NMD• want to deter the U.S. from threatening interests• even if ineffective, politicians might not believe it;

might worry that U.S. believes it is invulnerableRussia and China would react to NMD• countermeasures; more missiles/warheads;

higher alert rates; other modes of deliveryThese reactions could decrease U.S. security