Closing Time: Assessing the Iranian Threat to the Strait of Hormuz

0.15 MB·English

ClosingTime
Closing Time Caitlin Talmadge
Assessing the Iranian Threat
to the Strait of Hormuz
I
ranian closure of the
Strait of Hormuz tops the list of global energy security nightmares.1 Roughly
90 percent of all Persian Gulf oil leaves the region on tankers that must pass
through this narrow waterway opposite the Iranian coast, and land pipelines
do not provide sufªcient alternative export routes.2 Extended closure of the
strait would remove roughly a quarter of the world’s oil from the market,
causing a supply shock of the type not seen since the glory days of OPEC.
Even if the strait were not closed in the sense of being physically barricaded,
militaryconºictintheareacouldcausepricestoskyrocketinanticipationofa
supply disruption—and to remain high until markets could be assured that
the ºow of commerce had been restored. Consider that when Iraq invaded
CaitlinTalmadgeisadoctoralcandidateinpoliticalscienceattheMassachusettsInstituteofTechnology,
wheresheisamemberoftheSecurityStudiesProgram.Duringthe2007–08academicyear,shewasafellow
attheJohnM.OlinInstituteforStrategicStudiesatHarvardUniversity.
Theauthorwouldliketoacknowledgethehelpfulfeedbackshereceivedontheresearchandwrit-
ingofthisarticlefrommembersoftheSecurityStudiesProgramattheMassachusettsInstituteof
Technology(MIT),especiallyMichaelGlosny,BrendanGreen,LlewelynHughes,ColinJackson,
Jon Lindsay, Austin Long, and Barry Posen; the participants in a workshop on the Strait of
HormuzattheLyndonB.JohnsonSchoolofPublicAffairsattheUniversityofTexasatAustinin
August2007;thestaffoftheMITGeographicInformationServicesLaboratory;participantsinthe
MIT workshop Energy and National Security in the Persian Gulf in February 2008, especially
EugeneGholz,EvanMedeiros,andDarylPress;SteveLehotskyandVipinNarang;andtheanony-
mousreviewers.
1. SeeJohnDeutchandJamesR.Schlesinger,NationalSecurityConsequencesofU.S.OilDependency,
IndependentTaskForceReport,No.58(Washington,D.C.:CouncilonForeignRelations,2006),
pp.23,68;andEricV.Larson,DerekEaton,PaulElrick,TheodoreKarasik,RobertKlein,Sherril
Lingel,BrianNichiporuk,RobertUy,andJohnZavadil,AssuringAccessinKeyStrategicRegions:To-
wardaLong-TermStrategy(SantaMonica,Calif.:ArroyoCenter,RAND,2004),p.xvii.
2. In2006approximately17millionbarrelsperday(bbl/d)ofoiltransitedtheStraitofHormuz.
Thereisonlyonepipelinealternative,whichrunseasttowestacrossSaudiArabiatotheRedSea
portofYanbu.Itscapacityisonlyabout5millionbbl/d,andaboutaquarterofthatisinuse,leav-
ingslightlyfewerthan4millionbbl/dofslack—hardlyenoughtocompensateforclosureofthe
strait.TheUnitedArabEmiratesisplanningtobuildapipelinecarryingitsoiltoaportintheGulf
ofOman,butthispipelinewouldcarryonly1.5millionbbl/d.OtherPersianGulfcountriesperi-
odicallyexpressinterestinbuildingalarger5millionbbl/dpipelinethatwouldenablethemto
bypassthestraitandofºoadoilatOman.Detailsonitspotentialrouteremainunresolved,and
buildingitwouldtakemorethanadecade.Plansforsuchpipelineshavefallenthroughinthe
past.“GulfGovernmentsPlanOilPipelinesThatCouldLessenPossibleIranianThreats,”Associ-
atedPressFinancialWire,March20,2007;“NewsinBrief,”PetroleumEconomist,December1,2006,
p. 40; and Energy Information Administration, “Persian Gulf Region,” Country Analysis Briefs
(Washington,D.C.:U.S.DepartmentofEnergy,June2007),http://www.eia.doe.gov/emeu/cabs/
pgulf.html.
InternationalSecurity,Vol.33,No.1(Summer2008),pp.82–117
©2008bythePresidentandFellowsofHarvardCollegeandtheMassachusettsInstituteofTechnology.
82
Closing Time 83
Kuwait in 1990, temporarily halting the export of oil in both countries, the
world price of oil more than doubled merely on the expectation of future
shortages.AlthoughexcessglobalsupplycombinedwithincreasedSaudipro-
duction helped lower the price within a few months, it did not return to the
preinvasionlevelfornearlyayear.3Blockageofthestraitwouldposeavastly
greaterthreattotheºowofgulfoil,andatatimewhenexcessglobalcapacity
is lower and the price of oil higher.4
YetcouldIranclosetheStraitofHormuz?WhatmightprovokeIrantotake
anactionsocontrarytoitsowneconomicinterests?DoesIranpossessthemili-
taryassetsneededtoengageinacampaigninthestrait,andwhatmightsuch
a campaign look like? Perhaps more important, what would the U.S. military
havetodotodefendthestraitintheeventofIranianinterferencethere?What
would be the likely cost, length, and outcome of such efforts?
Despite consensus on the importance of the strait, no open-source analysis
has attempted to answer these questions systematically.5 Some analysts take
theIranianabilitytoblockthestraitasagiven,whereasothersareequallycon-
ªdent the United States’ military superiority would deter or quickly end any
Iranian campaign.6 One observer argues that “countering any Iranian block-
ade might involve only a few days of ªghting, with major disruption to ship-
pinglastingonlyslightlylonger.”7AnotherwarnsthattheUnitedStatesmight
havetoengageinweeksormonthsofmilitaryoperationstoopenanddefend
thestrait.8AnthonyCordesman,ahighlyrespectedexpertonthePersianGulf,
3. FranciscoParra,OilPolitics:AModernHistoryofPetroleum(London:I.B.Tauris,2004),pp.305–
306.
4. Ontheeconomicimpactofoilprices,seeJamesD.Hamilton,“OilandtheMacroeconomysince
WorldWarII,”JournalofPoliticalEconomy,Vol.91,No.2(April1983),pp.228–248;andDonaldW.
Jones,PaulN.Leiby,andInjaK.Paik,“OilPriceShocksandtheMacroeconomy:WhatHasBeen
Learnedsince1996,”EnergyJournal,Vol.25,No.2(April2004),pp.1–32.
5. One exception is Anthony H. Cordesman, “Iran, Oil, and the Strait of Hormuz,” CSIS Brief
(Washington,D.C.:CenterforStrategicandInternationalStudies,March26,2007),pp.1–7.
6. Fortheformer,seeSimonJenkins,“IfThisIsAhmadinejad’sBluff,ItIsBluffWorthCalling,”
Guardian,May10,2006;andJamesJayCarafano,WilliamW.Beach,ArielCohen,LisaCurtis,Tracy
L.Foertsch,AlisonA.Fraser,BenLieberman,andJamesPhillips,“IfIranProvokesanEnergyCri-
sis:ModelingtheProbleminaWarGame,”CenterforDataAnalysisReport,No.07-03(July25,
2007), http://www.heritage.org/Research/EnergyandEnvironment/cda07-03.cfm. For the latter,
seeDennisBlairandKennethLieberthal,“SmoothSailing:TheWorld’sShippingLanesAreSafe,”
ForeignAffairs,Vol.86,No.3(May/June2007),pp.7–13.
7. SimonHenderson,“FacingIran’sChallenge:SafeguardingOilExportsfromthePersianGulf,”
PolicyWatch,No.1112(Washington,D.C.:WashingtonInstituteforNearEastPolicy,June7,2006),
http://www.washingtoninstitute.org/templateC05.php?CID?2477.
8. Joris Janssen Lok, “Western Navies Eye New Tech to Defeat Mines,” Aviation Week & Space
Technology,April27,2007,http://www.aviationweek.com/aw/generic/story_generic.jsp?channel
?dti&id?news/dtMINE0407.xml&headline?Western%20Navies%20Eye%20New%20Tech%20to%2
0Defeat%20Mines.
International Security 33:1 84
concludesthat“Irancouldnot‘closetheGulf’formorethanafewdaystotwo
weeks,” although what leads him to this conclusion is unclear.9 Meanwhile,
the director of the Defense Intelligence Agency, Vice Adm. Lowell Jacoby,
testiªedin2005thatIranhassomecapabilityto“brieºyclose”thestrait,with-
out deªning what “brieºy” means.10 In short, analysts disagree about the po-
tential likelihood, course, and outcome of U.S.-Iranian conºict in the Strait of
Hormuz,butthenatureofcurrentdebateonthesubjectmakesithardtoascer-
tain the basis of differing assessments, much less determine which might be
correct.
Thisarticleattemptstoremedythesedeªcitsthroughanopen-sourceanaly-
sis of the potential interaction of Iranian and U.S. military forces in the strait.
Thistypeofanalysishasitslimits.Itcannotdrawonclassiªedinformation.It
cannotsaymuchaboutintentions,onlyapparentcapabilities.Itcannotpredict
howaparticularwarwillturnout,becausesuchoutcomesoftendependona
hostofnonmilitaryfactors.Whatitcandoisencouragerigorinthepublicde-
bates that inevitably occur, by showing how different assumptions and data
aboutmilitarycapabilitiesgeneratedifferentpredictionsabouttheparameters
ofpotentialconºict.Fromtheseresultscomedifferentpolicyimplications.An-
alystsmaystilldisagree,butatleasttheyandthoselisteningtothemcanascer-
tain the basis of their differences.
The analysis presented here suggests that the notion that Iran could truly
blockadethestraitiswrong—butsotooisthenotionthatU.S.operationsinre-
sponse to any Iranian action in the area would be short and simple. The key
question is not whether Iran can sink dozens of oil tankers, which would be
difªcult. Tankers are resilient targets. Their immense size, internal compart-
mentalization, and thick hull plates allow them to survive hits by mines and
missilesthatwouldsinkwarships.Theircrudeoilabsorbstheimpactofanex-
plosion and is difªcult to ignite.11 Historically, their captains have proven re-
ceptive to the strong ªnancial incentives to sustain shipping.12
ThequestioniswhetherIrancanharassshippingenoughtopromptU.S.in-
terventionindefenseofthesea-lanes.GiventhattheUnitedStateshasstaked
9. AnthonyH.CordesmanandMartinKleiber,Iran’sMilitaryForcesandWarªghtingCapabilities:
TheThreatintheNorthernGulf(Washington,D.C.:CSISPress,2007),p.201.
10. ViceAdm.LowellE.Jacoby,“CurrentandProjectedNationalSecurityThreatstotheUnited
States,”testimonybeforetheSenateSelectCommitteeonIntelligence,109thCong.,1stsess.,Feb-
ruary16,2005,http://www.investigativeproject.org/documents/testimony/317.pdf.
11. Martin S. Navias and E.R. Hooton, Tanker Wars: The Assault on Merchant Shipping during the
Iran-IraqCrisis,1980–1988(NewYork:I.B.Tauris,1996),p.86.
12. Ibid.
Closing Time 85
its credibility on promises to do just that, this is a threshold that Iran’s sig-
niªcant and growing littoral warfare capabilities can cross, even with fairly
conservative assumptions about Iranian capabilities.13 In particular, Iran pos-
sesses a larger stockpile of missiles and mines ten times as powerful as those
usedinthetankerwarsofthe1980s,thelastperiodofsustainednavalconºict
in the gulf. If Iran managed to lay even a relatively small number of these
mines in the strait, the United States certainly would act to clear the area. But
the experience of past mine-warfare campaigns suggests that it could take
manyweeks,evenmonths,torestorethefullºowofcommerce,andmoretime
still for the oil markets to be convinced that stability had returned.
More important, once the United States decided to clear the strait of mines,
the potential for further military escalation would be high, especially given
U.S. casualty sensitivity. The United States’ mine warfare assets are designed
to be used only in permissive—that is, nonthreatening—environments. The
UnitedStateswouldwanttolocateanddestroyanysourcesofIranianªreon
its mine countermeasure (MCM) ships. In particular, it would want to elimi-
nate Iran’s land-based, antiship cruise missile (ASCM) batteries and targeting
radars, which are mobile and likely protected by Iranian air defenses. The ae-
rial hunt for these assets could add days, weeks, or even months to the time
needed to clear the strait, and quickly develop into a large and sustained air
and naval campaign, depending on Iran’s strategy for expending the missiles
and its skill in hiding the batteries and radars. The United States might then
face the dilemma of continuing this difªcult search, or ending it by engaging
in an even broader coercion campaign against other targets in Iran or escalat-
ing to the use of ground forces. These options would be about as palatable to
the United States as they would be comforting to the world oil markets.
Thisarticleproceedsinªveparts.Theªrstsectionprovidesbackgroundon
the strait’s geography and how and why Iran might take advantage of it to
conduct an integrated littoral campaign using mines, antiship cruise missiles,
andland-basedairdefense.Thenextthreesectionsanalyzeeachofthesecom-
ponentsofapotentialIraniancampaign,aswellaspotentialU.S.responsesto
them.Thefocusisoncurrentcapabilities,althoughthearticlenoteshowplau-
siblefuturechangeswouldaltertheanalysis.Theconcludingsectiondiscusses
the implications for U.S. policy toward Iran and U.S. force structure more
generally.
13. OnU.S.promises,seeDavidE.Sanger,“OnCarrierinGulf,CheneyWarnsIran,”NewYork
Times,May11,2007.
International Security 33:1 86
Background
The Strait of Hormuz is the sole waterway leading out of the Persian Gulf.
All tankers carrying oil must pass through it to deliver or retrieve oil from
Persian Gulf ports. Iran controls the strait’s northern coast, while Oman and
the United Arab Emirates own the southern coast. The entire strait is only
180kilometerslong,andatitsnarrowestpointsonlyabout45kilometerswide.
It contains two shipping lanes used for large vessels. The channels are each
3.2 kilometers wide, with a 3.2-kilometer buffer zone between them. The
northern channel is within only a few dozen kilometers of the Iranian coast.
The coast contains few major cities but many small towns connected by
paved and gravel road networks. Most of the coastal terrain near the strait
consists of ºat beaches followed by the beginnings of the Zagros mountains.
Its ridges go several hundred kilometers inland and range up to about 2,000
meters in height, with valleys in between. The terrain opposing the eastern-
most portion of the strait is considerably ºatter, although there are still some
elevations up to about 1,500 meters.14 The climate is generally hot, with vary-
ing degrees of visibility. Sandstorms are not uncommon inland, and high hu-
midityoverthegulfand1to2milesinlandcanleadtosigniªcantcloudcover.
the iranian navy
Iran’s regular navy includes 18,000 active-duty sailors, as well as another
20,000intheIslamicRevolutionaryGuardCorpsNavy(IRGCN).15Iranisnot
lackinginlocationsfromwhichtoinitiatenavalcombatinthegulf,especially
theStraitofHormuz.Thenavyhasbasesallalongthecoast,includingalarge
navalairstationandoperationalheadquartersatBandarAbbasdirectlynorth
of the strait. Iran also has nearly a dozen domestic ports facing the strait, and
the IRGCN has military outposts on islands close to the strait: Abu Musa,
Larak, and Sirri. Iran uses these islands as forward bases for in-shore patrol
craft. Presurveyed missile and air defense sites are also visible in satellite im-
ageryofthesoutherncoastofLarak,facingthestrait.Iranclaimstwootheris-
14. InformationtakenfromIRAN2004,roadmapofIranbyGitashenasiGeographicalandCarto-
graphic Institute, available from author; Google Earth; Michael Eisenstadt, “Iranian Military
Power:CapabilitiesandIntentions,”PolicyPaper,No.42(Washington,D.C.:WashingtonInstitute
forNearEastPolicy,1996),pp.61–62;and“SouthwestAsiaI:Iran,Iraq,Kuwait,andSaudiAra-
bia,”editionC,InterschoolSubcourseIS3008(FortHuachuca,Ariz.:U.S.ArmyIntelligenceCen-
ter, March 1999), http://www.globalsecurity.org/military/library/policy/army/accp/is3008/
index.html.
15. International Institute for Strategic Studies (IISS), “The Middle East and North Africa,” The
MilitaryBalance,2008(London:IISS,2008),p.243.
Closing Time 87
lands, the Greater and Lesser Tunbs, which sit between the channels in the
west. Additionally, Iran controls Qeshm, a large populated island about a
dozen kilometers off its coast, directly adjacent to the strait.16
motives for action in the strait
Historically, Iran has recognized that closing the strait would be the military
equivalentofcuttingoffitsnosetospiteitsface.Notonlywouldsuchamove
deprive Iran of vital oil revenue, but it also would invite international inter-
vention.Evenduringthe1980–88Iran-IraqWar,whenIransoughttoblockthe
passage of oil tankers to and from the Arab states, it exercised restraint. It at-
tackedshippingprimarilyinthewesterngulf,closertotheShattal-Arab.Only
there and in United Arab Emirate waters did Iran lay mines, and not in large
numbers.Itsactivitiesinandaroundthestraitwereconªnedtointrusiveship
boardingsandinspectionsofcargoboundforIraq.TheIRGCNoftenfollowed
thisactivitywithnight-timesmallarmsªreatshipsencounteredtheprevious
day. Late in the war, Iran installed ASCM batteries at several locations facing
the strait, but it never ªred them at trafªc in the area—even after the U.S.S.
Vincennes accidentally shot down an Iranian passenger airline in 1988.17
Many events catastrophic enough to drive Iran to block the strait—say, a
U.S.nuclearattackontheIranianhomeland—alsowoulddestroymanyofthe
Iranianmilitarycapabilitiesneededtoundertakethecampaign.Recentmedia
leaksindicatethatevenaconventionalU.S.attackonIraniannuclearfacilities
would be designed in such a way as to preemptively destroy the majority of
the assets needed to lash out in the strait.18 That said, a more limited U.S. at-
tackoranIsraeliattackmightproduceavengefulIranwhosenuclearprogram
was decimated but whose other military assets remained intact.19 Indeed,
there is little evidence that a 2007 U.S. National Intelligence Estimate allayed
IsraelifearsabouttheIraniannuclearprogram,anditmayevenhavemadean
Israeli attack more likely by taking the political wind out of U.S. involvement
insuchanoperation.20Moreover,avocalminorityintheUnitedStatescontin-
16. Informationonbasenamesandwhichorganizationcontrolsthemisfromibid;physicalloca-
tionofbasesisfromIRAN2004;andmeasurementsandotherobservationsaretakenfromGoogle
Earth.
17. NaviasandHooton,TankerWars,pp.37–38,58,81,109–112,122–123,174.
18. SeymourM.Hersh,“TheIranPlans,”NewYorker,April17,2006,p.30.
19. ThefeasibilityofanIsraeliattackofthistypeisdiscussedinWhitneyRaasandAustinLong,
“OsirakRedux?AssessingIsraeliCapabilitiestoDestroyIranianNuclearFacilities,”International
Security,Vol.31,No.4(Spring2007),pp.7–33.
20. National Intelligence Council, “Iran: Nuclear Intentions and Capabilities,” National Intelli-
gence Estimate, November 2007, http://www.dni.gov/press_releases/20071203_release.pdf; and
International Security 33:1 88
uestoinsistontheneedformilitaryattacksonIran’sprogram,andasthereal-
ity of attempted Iranian proliferation eventually reregisters with the U.S.
public, political support for attacks may regain steam.21
IftheUnitedStatesorIsraelattackedIran,therestraintthatpreviouslychar-
acterizedIranianbehaviorinthestraitmightevaporate.Indeed,in2006Iran’s
supremeleader,AyatollahAliKhamenei,cautionedthatalthoughIranwould
not be “the initiator of war,” if the United States punished or attacked Iran,
then“deªnitelytheshipmentofenergyfromthisregionwillbeseriouslyjeop-
ardized.”22 The Iranian oil minister made similar comments, hinting that “if
the country’s interests are attacked, we will use all our capabilities, and oil is
oneofthem.”23OnecanimagineothereventsthatcouldbringIrantothesame
point of desperation—for example, if it were losing a conventional war with
any of its neighbors and wanted to open another front as a punitive measure
oradistraction.ShortoftheextremecaseinwhichtheUnitedStatespreemp-
tively destroys much of Iran’s military, there is an intermediate range of sce-
nariosinwhichIranisdeeplythreatenedyetpartsofitsmilitaryarestillintact
and functioning. It is in this context that threats to block the strait could be-
come reality.
a scenario for closure
How might Iran take advantage of existing military installations and assets
andthestrait’sgeographytoattempttoblocktheºowofoil?Suchacampaign
woulddependonIran’sabilitytocoordinatetheuseofmines,ASCM,andair
defensetocreatealittoraltrapfortheUnitedStates.Itwouldseektodotothe
United States in the strait what the Turkish and Germans did to the British in
theDardenellesin1915:mineanarrowpassageway,then,fromwell-defended
coastal positions, attack those trying to clear the mines.24 Speciªcally, Iran
would want to begin by laying mineªelds in and around the strait’s shipping
channels,aswellasusingantishipcruisemissilesagainstmerchanttrafªcand
any U.S. MCM and convoy vessels.
Facingthistrap,theUnitedStatescouldemploytwoassetsinthestraitthat
RoryMcCarthy,“UnilateralMilitaryStrikeStillanOption,SeniorMinistersInsist,”Guardian,De-
cember8,2007.
21. Norman Podhoretz, “The Case for Bombing Iran,” Commentary, Vol. 123, No. 6 (June 2007),
pp.17–23.
22. QuotedinAliAkbarDareini,“AyatollahWarnsWestagainstAction,”AssociatedPress,June
5,2006.
23. Quoted in Ariel Cohen, James Phillips, and William Schirano, “Countering Iran’s Oil
Weapon,”Backgrounder,No.1982(Washington,D.C.:HeritageFoundation,November13,2006),
http://www.heritage.org/Research/Iran/bg1982.cfm#_ftnref4.
24. JamesA.Meacham,“FourMiningCampaigns:AnHistoricalAnalysisoftheDecisionsofthe
Commanders,”NavalWarCollegeReview,Vol.19,No.10(June1967),p.78.
Closing Time 89
theBritishlackedintheDardanelles:sophisticatedsurfacedefensesandoffen-
sive airpower against enemy ªre positions ashore.25 An air campaign could
workinconcertwithsurfaceactiongroupstodestroyIran’sASCMcapability
while suppressing or destroying Iranian air defenses. The United States’ goal
wouldbetoclearthemines,areasonablystraightforwardtechnicaltask,while
Iran’s goal would be to make success in that endeavor contingent on much
more complicated tasks, such as ºeet defense and the hunt for mobile targets
inland. The potential collision between these goals is the subject of the next
three sections of the article.
Mine Warfare in the Strait of Hormuz
Iranpossessesanadequateinventoryofminesandmultipleplatformsforde-
livering them. The key variable is not the number of mines Iran possesses,
however—minesarerelativelycheaptoprocure—butratherhowmanyitcan
laybeforebeingdetected.ProjectionsbasedonpastinstancesofU.S.MCMop-
erations indicate that it could take a month or more to reopen the Strait of
Hormuz if Iran were allowed to initiate even a small mine-laying campaign.
iranian mine warfare platforms
Iran could lay mines from any of its 3 frigates, 2 corvettes, and 10 fast missile
boats.26Iranalsohas3shipsinthePersianGulfthatappeartohavededicated
mine-laying capabilities, plus 3 still-functioning RH-53D Sea Stallion mine-
layinghelicopters.27Additionally,Iranpossessesmorethan200smallerpatrol
andcoastalcombatantssuitableforminelaying.Thesearefaster,hardertode-
tectwithradar,andusefulmainlyforrocket,recoillessriºe,andsmallarmsat-
tacks. Iran used small craft of this type to lay mines during the tanker wars.
Iran has 3 relatively modern type-877 Kilo-class diesel-electric submarines
from Russia. Each Kilo has six 533-millimeter torpedo tubes. The subma-
rines can carry 18 torpedoes or 24 mines.28 Iran is also said to have at least 1
midget submarine capable of laying mines, although few other details are
known.29Ingeneral,theIranianoperationalrecordwithsubmarineshasbeen
spotty, and they are also overdue for reªts.30
25. Ibid,p.81;andMichaelE.Golda,“TheDardanellesCampaign:AHistoricalAnalogyforLitto-
ralMineWarfare,”NavalWarCollegeReview,Vol.51,No.3(Summer1998),pp.82–96.
26. IISS,TheMilitaryBalance,2008,pp.242–244.
27. CordesmanandKleiber,Iran’sMilitaryForcesandWarªghtingCapabilities,pp.119–120.
28. IISS,TheMilitaryBalance,2008,pp.242–244.
29. Jane’sUnderwaterWarfareSystems,2006–2007,18thed.(Surrey,U.K.:Jane’sInformationGroup,
2006),p.11.
30. Jane’sFightingShips,2006–2007(Surrey,U.K.:Jane’sInformationGroup,2006),p.355.
International Security 33:1 90
It would be challenging, though not impossible, for Iran to use its subma-
rinesforminelayinginthestrait,duetoseveralfactors.First,theunderwater
geography of the strait neutralizes many of the characteristic advantages of
submarines.Kilosrequireaminimumoperatingdepthof45meters,andonly
inafewplacesisthewaterinthestraitmorethan80metersdeep,limitingthe
use of tactics such as diving for concealment or protection. Additionally, the
highsaltcontentofgulfwatersandotherfactorscreateheatcurrentsthatdis-
turb sonar. As a result, it is harder for submarines to use passive sonar to de-
tect ships without revealing their own location. Submarines become hidden
butirrelevantplatforms,orusefulplatformsthatareeasiertoªnd.Eitherway,
antisubmarinewarfareforcesgainanadvantage,andU.S.ASWpatrolsinthe
gulf would be likely to detect mine-laying activity by Iranian submarines.31
ThereisevidenceIranmayhaverealizedtheseproblemsandisplanningtore-
locate its submarines to the Gulf of Oman.32
iranian mines
Iranisbelievedtopossessatleast2,000mines.33Byhistoricalstandards,thisis
not a large stockpile. For example, the British and Americans laid more than
70,000 mines in an effort to seal the North Sea against German U-boats in
WorldWarI,andtheUnitedStatesandtheSovietUnioneachstockpiledhun-
dreds of thousands of mines during the Cold War.34 Nevertheless, even small
numbers of mines have been able to halt surface trafªc when their presence
was known. In 1972 the United States immediately stopped all trafªc in and
out of North Vietnam’s Haiphong Harbor with an initial drop of only 36
acoustic-magnetic mines.35 In 1991 the Iraqis were able to discourage a U.S.
amphibious invasion by laying only 1,000 mines off the Kuwaiti coast, 2 of
whichlaterhitbutdidnotsinkU.S.warships.36In1950theNorthKoreansde-
layedtheU.S.landingatWonsanbylayingonly3,000minesacross50square
miles.37 As these examples show, mines derive much of their power from the
31. Anthony H. Cordesman, Iran’s Developing Military Capabilities (London: Sampson Low,
Marsten,May2005),pp.62–63.
32. Jane’sFightingShips,p.355.
33. Thisistheªgurereportedinmostsources.Jane’sFightingShipsclaimsthatIranmayhave“up
to3,000mines.”Ibid.,p.354.
34. Meacham,“FourMiningCampaigns,”p.91.
35. TamaraMoserMelia,“DamntheTorpedoes”:AShortHistoryofU.S.NavalMineCountermeasures,
1777–1991(Washington,D.C.:NavalHistoricalCenter,1991),p.101.
36. MichaelR.GordonandBernardE.Trainor,TheGenerals’War:TheInsideStoryoftheConºictin
theGulf(NewYork:Little,Brown,1995).
37. Meacham,“FourMiningCampaigns,”p.105.
Closing Time 91
fear they induce, which is often based more on the psychological effect of a
lucky initial explosion than on rational calculations of risk.38
OfIran’s2,000mines,abouthalfwerepurchasedfromRussiawhenIranac-
quired its 3 Kilo submarines.39 It is hard to do more than guess at Iran’s spe-
ciªc stocks of different kinds of mines and which type(s) it would use in the
strait.40 The strait is relatively shallow, and the currents are strong, meaning
that drifting mines could be ºushed easily from the shipping lanes and/or
cometoposeadangertoIran’sownforces.Indeed,Iranianminesfoundinthe
western gulf during the 1980s apparently began their lives as moored mines
farthereastbutbrokefreeoftheirchainsintheroughwaters.Itisareasonable
assumption that Iran would have sought to acquire moored or bottom mines
to use in the strait if at all possible.41
In the past Iran has used the North Korean–manufactured M-08 moored
contact mine, which is based on a 1908 design. The U.S. Navy caught the
IRGCN red-handed laying such mines north of Qatar in 1987.42 One blew a
holeintheKuwaitisupertankertheBridgetonin1987,anotherinthehullofthe
U.S.S. Samuel Roberts frigate in 1988. (Neither sank, though they required ex-
tensiverepairs.)TheM-08hasa115-kilogramcharge,ismeantforuseagainst
surface ships, and can operate in depths of 6 to 110 meters, making it feasible
for use in the strait.43
TheSovietNavyproducedlargequantitiesoftheM-08andthesimilarM-26
mine,soitisplausiblethatRussiacouldhavesoldIransomeofeachwiththe
recentsubmarinesale.NeithertheM-08northeM-26canbelaidfromtorpedo
tubes,however,soatleastsomeofthe1,000minesRussiasoldIranwerelikely
of a different sort—probably from Russia’s MDM/UDM series of seabed
inºuence mines.
Versatileandpowerful,theMDM-6isalikelycandidate.Itcanbelaideither
from 533-millimeter torpedo tubes (the tube width found on Iran’s Kilos) or
38. Ibid.,p.113.
39. Cordesman,Iran’sDevelopingMilitaryCapabilities,chap.4.
40. Ibid.;andJane’sUnderwaterWarfareSystems,p.365.
41. For background on mines, see Thomas R. Bernitt and Sam J. Tangredi, “Mine Warfare and
Globalization:Low-TechWarfareinaHigh-TechWorld,”inTangredi,ed.,GlobalizationandMari-
timePower(Washington,D.C.:NationalDefenseUniversityPress,2002),pp.391–397;andGaryK.
Hartmann, Weapons That Wait: Mine Warfare in the U.S. Navy (Annapolis: Naval Institute Press,
1979).
42. Melia,“DamntheTorpedoes,”p.126.
43. Jane’sUnderwaterWarfareSystems,pp.362–364.Iranalsopossessesanunknownquantityofthe
M-26mooredcontactmineandthesmallerMYaMmooredcontactmine.Jane’sUnderwaterWarfare
Systems,pp.362,364;andEisenstadt,“IranianMilitaryPower,”p.55.ReportspersistthatIranhas
triedtoacquireorindigenouslyproducetheEM-52orMN-52rocket-propelledmineaswell.