American Cryptology: Two Centuries of Tradition

Although

the National

Security

Agency

is only thirty

years

old

(estab-

lished by order

of President

Harry S.

Truman

in

1952), the

functions

it

performs

have been

part

of

human

history

for thousands

of

years.

The

need

to

safeguard one's

own communications

while attempting

to

produce

intelligence

from

foreign communications

has long been

a

recognized

part

of

governmental

activity.

In the American experience,

cryptologic

efforts

can

be

traced

to

the

very

beginnings

of the American

nation. George

Washington

employed

Elbridge

Gerry

(later

Vice

President

of the

United Statee)

to solve

the

suspected

cryptograms of a

Tory spy,

Dr. Benjamin

Church.

Thomas

Jefferson

included the

making of codes

and ciphers

among

his

many interests,

putting

his efforts

to

use in

both

private

correspondence

and

public

business.

One

of

his

inventions, the cipher

wheel,

has been

described

as being

in

"the

front

rank" of cryptologic

inventions.

The

American

Civil War

created

a new

urgency

for techniques

in both

cryptography

(the

manufacture of

codes

and ciphers)

and

cryptanalysis

(the

breaking

of

codes and ciphers).

It aleo

introduced

new elementa

into both

processes

-

telegraphy

and

sigrrificant

advances

in the

use of

signal

flags

and

torches. These

methods of

transmitting

information

permitted

rapid

communication

from

one outpost

to another

or

from a commander

to

his

subordinates, but

also

brought

with them

new

dangers of

the

loss of that

information to an enemy.

Both sides

considered

telegraph

lines

major

targets

and attempted either

to cut or

tap them.

Cryptology

again

proved

to be

of

great

sigrrificance

in the First

World

War,

as evidenced by

British

decryption

of the

famous

Zimmermann

Telegram. In an

effort to keep

the United

States

from

playing

an effective

role

in the war

in

Europe,

Germany

offered

Mexico

the

opportunity

to

regain Texae

and other territories

lost

to the United

States

during the

nineteenth

century,

in return for a

Mexican

declaration of

war against

the

U.S.

The telegram

backfired, as

its

release by British

authorities

brought

the U.S.

closer to

war with Germany.

Tactically,

the

First World War

introduced

wireless communications

to the battlefield,

increasing flexibility

but

making

codes

and ciphers even

more eseential

in

guaranteeing

eecurity.

U.S.

Army

cipher

device

M-94, developed

in the

1920s. The

M-94

was

virtually

identical in

principle

to Jefierson's

cipher

wheel.

German Enigme, Four-Wheel

Naval Model.

After the armistice of 1918, the United Statee maintained

modest

but

significant

cryptologic establishments

in

the Navy and War

Departments,

along

with

an

interdepartmental

effort conducted in New York

and headed

by Herbert O. Yardley.

In

1929

Secretary of State

Henry

Stimson

withdrew

financial

support for Yardley's

"American

Black Chamber," and commu-

nications security

(COMSEC)

and communications intelligence

(COMINT)

became once

again a largely

military

function.

Under

the direction of

William F. Friedman, the Army's

Signal Intelligence Service and

its

Navy

counterpart, Op-20G,

overcame limited resourcee

to

make truly outstanding

contributions

to cryptologiy. By the

time the United States entered

the

Second World War, American

cryptologists had

penetrated

Japanese

diplomatic

ciphers, and during

the

war

aesisted their Britieh colleagues

in

the exploitation

of German communications, while

at

the eame

time

providing

secure

communications

equipment for American commanders

and

policy

makers. In

actions ranging from the

great

naval battles

of the

Pacific

to the invagions of

North

Africa

and Western Europe, American

crypta-

nalysis

and cryptography

provided

information vital

to the eventual

Allied

victory.

The

pootwar

era

opened with an emphasis on

"economy

and efficiency,"

resulting in

cutbacks

in

all areae of

national defense, including COMINT

and

COMSEC. In some ways, this belt

tightening

proved

beneficial,

as

steps were

taken to eliminate

duplication and adapt the

cryptologic

egtablishment to the realitiee of America's

poeition

as a

permanent

world

power.

The creation of the

Department of

Defense

and

the Central

Intelligence

Agency reflected the

desire for unified national coordination

and direction

of important defenee and security

matters. In 1949, hesident