.. _,., 

REF ID:A39176 

~IE PO'm1rD.LITIES OF CC!mfl AS A SOUBCB i 

OF tJAremD Qli!. TIIE II!tmElllE 00' H<Bm..InFB 

l. The value to the Allies ot wr Signal Intell.1gmce ettm:'t ~ 

lfca-ld uar n can acarcel;r be overestlmted. Through the readina ot bighgrade German and Japamse cipbm.'EI, we wro able to penataiate the 8Dl!IQ' 

liDes and enter the llea.dlplrters of' High Ocm.umds1 A1'DLV' Groups, am 

Al'miese On a strategic. levelt •special lntol.lia8l'JO$nJ.-was tbs un1qua 

I source of' advame knowled«o Of' tbe e~s plans for bath ot.tenaiw and 

dat"ensive operations. It was tho t:b.leliest, mast camplete, am :most 

rellable source of intellig~e on hie~ pf ~ttJ.e1 intentlaaaa and 

oapaM11:tJ.es. " ... 

On the tactical level.1 na4'ng of madium and ~ ciphara; 

traffic a.ml1'sis1 and dil'ection-.tmling provided a np1d flow of' operational. intell:igeme in the field. The value of oparatilona1 intellig&Dce 

from those sources vas prCWld again dnr1ng the confU,ct 1D Korea, and 

the vital part wh1ch COi-1Ilf?4' vil1 p.'l.Q'. tn the 8V8Dt of a th1z'd WOl"ld war 

Gt reasonabJ1' conventional duration eamot now be in •l\V' aer.loua doubt. 

The role of COMI?ll as a smrce ot acivance 1l8rD1tJg Of the outbreak of· such a var 181 hovanr1 ~ problama.ttc. · 

1 The wart.4me cover name for 1ntelligeim$ resultlng .fror.i auccasatul. C1'7PtanalJ1;1c attack an bigh-grade cipher BJ'8tem8e 

J 2 The tam COMINT, as it :la used toda;r, incl.mes both the "Speed.al Intalligenoe•• of'· World War II and aU o1her 1ntalligeme which ml'I' be daJ:iivacl 

.franl. the radio comnam:1cat1ons act1v.l.t1es of a tonign govarmant • 

medium and low-grade cipher messages, p1a1n language tnnsmlssions1 ftdio 

tel.aphone conversations, tntf1c anal.JBia, am ctlrection-~. · 

EO 3.3(h)(2) 

PL 86-36/50 USC 3605 

Declassified and approved for release by NSA on 01-09-2014 pursuant to E.O. 1352e 

NSA F-711.CIOS I .M 52 TOP SECRET CP.~NOE 
REF ID:A39176 

.. 

.,~ 

2· // 

EO 3.3(h)(2) 

PL 86-36/50 USC 3605 

" ... •. f I 0 •• I I I •• ' I °' I I "''II: I I. 1• 
l,J 

J 

.. 

' ,1/ 

REF ID:A39176 

1 A Rudi' ~f the ocmdiact at oparat.iODa on the Eutarn '1-ont m World War 

II provides us i.lao with O't"e1'1fh•1m1ng av:f.de.ace of the lengtba. to vbioh 

the Sodate vlll go·in· o1"de to gain· all the adra1ltagea ot :lnit.i.el. 

su.rpr.tae,. 

~ 

For ...-uple; in order to_dm1' the •aDT arq intormatian 

the f1N pl.In tor an attek 01) a smaU sector·: of the 

Finniah h'ont · Ruaaian unitS sp~ silt ~aka preparing thaU poa1tiom 

under the d1fkcult condittoJ:U1· of complete s~19 • Tha1r auccaaa vu 

such that tba G91"!Dll2S lost 7S% ot the1r total.icaaualtiea in the fim 

f:i:n minu.tea ot the artlller.r barrage. 

3 EO 3.3(h)(2) 

PL 86-36/50 USC 3605 

NSAF-Pll.C:IOS ''-'52 TOP SECRET 6A;NOE 
. .: • 

REF ID:A39176 

about to be launched &u"'8imt t.io United States. For, as tar ·as the U3SR 

is concerned, thooe $0Ul'U98 are plain text · 19seaaes and tratno ~. 

Plain lan~ r.JaSsagas contain onl.3' intomat1.on which :ls considaNcl by' the ~tor to be unclaasitiade They !f'lJ1' pl'O'Vida a strong · indication of widcapreal i..?1dustrial !lOb:Uizatton, or a sti-Jld.ne item,_ 

, 

. The sapb:lstica~ of Sov:Let security techniquaa haa been claai'll' deao~teclo During Uorld. war n. tho Saviots achitlnd no~ 

succeaaes in :radio deceptd.QP. The -~ tbat araaqa:l.D ol tba1r ndio 

trattJ.c, unsupported bT far more Positive evidence, will .reveal a •111-tegic intention cannot sari~ be -.iterta!Ded• . · 

!he potAmt4.~t4es of COHIU'l' which includes •Special~­

gence• require a completel.J' dltfarant evaluati~ 

. The potant1alities of a oa.mrr Ol'ganizatton vhlch dOes /J'Jot lack 

the mast important caimn source are so great that th4t dttftcultiea 

invol.ved :Sn prov1ding it with that aouroe ~ 8CU'Cel1' be c~ a 

deterrent factor. Hor should tba benefit.a wh:ll:h :Lt could iteaaonabl1' 

Ji PL 86-36/50 USC 3605 

EO 3.3(h)(2) 

'l'OP SECRET CANOE 
. . . . 

REF ID:A39176 

ldg• SECRET C1W~'1lst 'f01i SECftB! PL 86-36/50 USC 3605 2 11: · l9$J 

EO 3.3(h)(2) 

prmid.so ba cliDcounted on ~ crOlll1ds that such an oznmti.zat4on would 

not :laVO t110 cb:l>DDtnble cap:ilJAity of .turnish:l.n(; opac:l.tia lm"ninc th.at 

hostili 'M.es lmr& about to be in:i:tia~ It io beyond tllo power o1 arq 

coumr organizatl.on to guarantee in advance that it u1U pl:'Oduce a 

specitic piece of :lnfarmatLon• oime1 oven it it could obtrd.n and Nad 

all the msaagas o:r:!g:Lnatad ·bJ' .a i'ol'Oign nat4.on. still. it caald not wZ'ite tho. . 

1 I~~ in the .. eme of readable messages fl'Cm the .,a. tba 

nature and extent of tb.a\ bLdld up1 u, in fact, it did occur, bu 

not bean aet.t:Le4 by' ·tratf:lc ~ in five J98%'1i• 

s 

HM F- 711.C IOS I J.1 52 TOP SECRET Cl\NQF. 
REF ID:A39176 

. . 

the.t the evidonoe available was by' no ::ioano sutfioi.e"iit to gwl1"8111*e that 

the conclusion iras sound. 

PL 86-36/50 USC 3605 

EO 3.3(h)(2) 

6 

NSAF-711.CIOS IJ.152 TOP SECRET CANOE.