NMD-美国导弹防御计划.

NMD-美国导弹防御计划NATIONALMISSILEDEFENSEPROGRAM(a.k.a.StarWars)PrimaryObjectiveTheobjectiveoftheNationalMissileDefenseprogramistodevelopandmaintaintheoptiontodeployacosteffective,operationallyeffectiveandAnti-BallisticMissile(ABM)treatycompliantsystemthatwillprotecttheUnitedStatesagainstlimitedballisticmissilethreats,includingaccidentalorunauthorizedlaunchesorThirdWorldthreats.TheNationalMissileDefenseprogramcameintoexistenceduringtheearly1960whenscientistsandtechniciansworkedonsuchasystem,however,thelessfeasibleitseemed.In1972,PresidentRichardNixonandSovietleaderLeonidBrezhnevagreedtotheAnti-BallisticMissile(ABM)Treatywhichforbadebothsidesfromdeployinganationalmissile-defensesystem,andrestrictedthetestingwhichmightmakesuchasystempossible.BackgroundHistoryofNMDPresidentialAdministration’sAgendaforMissileDefenseReagan’sAdministration-DespitepassageoftheABMtreaty,theReaganadministrationtookupthecauseagainthe1980’s.Ultimately,theReaganadministrationspenttensofbillionsofdollarsonthedevelopmentofmissiledefensewhichthevastmajorityofscientistsknewcouldn’twork.Reaganpromiseda“nuclearshield”thatwouldachievean“ultimatesecurity”fortheAmericanpeople,suchasystemwasneverevenconceivable.BushAdministration-(Father)-proposedalimitedsystem,renamed“GlobalProtectionAgainstAccidentalLaunchSystem”.ThissystemwasproposedtoprotectAmericansagainstanaccidentallaunch.BushalsocalledforthedevelopmentofTheaterMissileDefenseprogramsagainstshorter-rangemissiles.BytheendoftheBushadministration,over$100billionhadbeenspentonanti-missileresearch,withvirtuallynothingtoshowforit.PresidentialAdministration’sAgendaforMissileDefenseTheClintonAdministration--deviseda“Three-Plus-Threeprogramwhichsupporteddevelopmentofanationalmissile-defensesystemoverthreeyears.Thisprogramsupporttheuseoftwentyground-basedinterceptors,whichcouldblockmissileslaunchedbyaccidentallaunches.However,ClintonplancouldnotprotecttheUnitedStatesfrommajorballistic-missilestrike.Estimatesofthesystem’scostrangedfrom$30to$60billion.TheBushAdministration(Son)--hascalledforearlydeploymentofanationalmissiledefensesystem.Thesystemsunderdiscussionincludethemid-course,land-basedsystemproposedbytheClintonAdministration,butalso“boost-phase”system,sea-basedsystems,expandedtheaterdefenses,outer-spacelasersystems,andnuclearsystems.ThecostoftheproposedsystemhasnotbeendetermineyetDesignTheNationalMissileDefensesystem,whenfullydeployed,wouldinclude1.Space-andground-basedsensorstoprovideearlywarningofattackingmissilesandtoinitiallyidentifyandtrackthem;2.Ground-basedradartofurtheridentifyandtrackthethreateningwarheadsandassesswhetherthesystemdestroyedthewarheads;3.Ground-basedinterceptors,eachconsistingofathree-stageboosterandpayload(calledakillvehicle)capableofguidingitselftocollidewithanddestroyincomingwarheads(aconceptcalledhit-to-kill)outsidetheearth’satmosphere;and4.Abattlemanagement,command,control,andcommunicationssystem.TheBasicsofBallisticMissileDefenseAllballisticmissileshareacommon,fundamentalelementThemissilesfollowaballistictrajectorywhichincludesthreephasesPhaseI---BoostPhasePhaseII–Mid-CoursePhasePhaseIII–TerminalPhaseTheBoostPhase---isthephaseinwhichthemissilehasbeenjustlaunchedandisthrustingtogaintheaccelerationneededtoreachitstarget.Thisphaseusuallylast3to5minutesandthemissileistravelingontherimoroutsidetheearth’satmosphere.ThePost-BoostPhase--DuringthisphasethemissilehasreleasedthelastofthereentryvehicleTheMid-CoursePhase---Duringthisphasethemissileisfreefallingtowardsittarget.Also,duringthephasethemissilesisarmingitselfwithitweapons(whichareknownaswarheads)Normallythisphasecanlastabout20minutes.TheFinalPhase---(a.k.a.theterminalphase)Duringthisphasethemissile’swarheadsrenterstheearth’satmosphereatincrediblespeeds,someatover2,000mpp.CostTodaytheUnitedStateshasspentroughly$122billiondollarsonvariousmissiledefenseprograms69billionhasbeenspentforresearchanddevelopmentofsuchapotentialsystem,ratherthanproduction.Theactualbuildingofthespace-basedsystemsproposedwillcostwellover$200billiondollars.010203040506070HealthCareMissileDefenseReganBush-FatherClintonBush-SonAmericanOpinionPollThetroublestheMissileDefenseSystemwillfaceLoworbitingsatelliteswillhavetofindandtrackwithpinpointaccuracycomplexwarheadstravelingat15,000mileswhicharesurroundedbydozensofdecoysThisinformationhastoberelayedtothebasecommandonthegroundAnti-ballisticmissilewillhavetobelaunchedwithinamatterofsecondstointerceptincomingmissiles.CurrentThreatstotheU.S.Infact,thethreattotheUnitedStateshasactuallyshrunk.CurrentlyRussiahasabout5,200missilewarheadsdeployedononethousandmissiles,adecreaseof52percentinthenumberofmissilessince1980,andthesedecreasesarelikelytocontinue.ChinahaspresentlysometwentyICBMs,aforcewhichisnotlikelytoincreaseunlesstheUnitedStatesdeploysanNMDsystem.Thethreatinintermediate-rangemissiles(threetofivethousandkilometers)hasvirtuallyendedduetothe1987treatybanningthem.Onlysixnations--Israel,SaudiArabia,India,Pakistan,NorthKorea,andIran--havemedium-rangemissiles(onetothreethousandkilomet