ETO, Logistical Build-Up in the British Isles

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SEcTIOX 13
PLAI31ING OP 50s TROOP BASIS *
48. Overdl Plmnin@ Seeis. The developnent of the $05 troop basis
fol.lowd closely the development ,Of the overall troop besie as disoussed
in sone detnil in Section 1 and 3, Chapter 2, above. In that discuseion
were reviewed the changing plcns for operatiore to he mmpted from the
British Isles and tllB resulting changes in troop bmie. Each change In
OVCrCdl troop basis necessitated a complete recalculation of service
troq reoui reaent s,
rXl& the early prt of 1942, requests for SOS personnel for
the Ttienter w8i.e besed antirely on the &dainistrRtive supuort of the
nubar- of groupd nnd p1r foice personnel to be phased in for protection
of the 3ritish Isles end the opening of the air offenaive.
During the 8u"r of 1942, the fimt reasonably complete troop
bpsis was established, based on pUma for invading the Continent in the
spriw of 1943, with an initial force of L,lk7,000Unitkd Statee troops.
l!?iis plm 'in6 cancelled by the invasion of North Africe. in november
1942,
In the autum of 1943, the SO5 troop requirement8 were recelculatcd
r.8 3 result of the decision of the Qpebec Conference to launch
the invnsion in 1944 with 1,L60,000U.S. troops. 3ut the recdculatian
we6 soon inval.i&atd when the pre-invasion troup basis was chenged wain
la Jenury 1944, a second tiiue in Februnry, and Q tlitrd tiue in bhrChl.
49. Difficulfies in X-raluAtIna the Problem. ,%ere !"e numerous
difficulties which tended bo hinder the intelligenb:.plaming of en RCcurate
SQS troop besis. nose difficulties asre generally the result of
incxporience on the part of the staff involved in the cnlculations, and.
of e. lock of apecific infomation as to future operrtions.
Unit1 the middle of 1943, the information furnished foi C~CU-
1BtiIq the SOS troop bmis !r89 incomplete, giving littb more than the
totd of troogs to be supported and raking acmt mention of ttie type of
operation. There :'m also 00me initial lack of underatanding between
the !lnr Deparfnent and ths Tha&ter with recard to Theatsr personnd needs
end the types of troops thph rould be evailnble from the -United States.
Until the latter part of 1943, when the First U.S. AIW oatabli6hed
hesdqudters in %and, no precedent hed Seen sct for cdculating
the nunbar of service troops required for asai@nmt to the Rrnies,
Rnd e.I.Tly requirements were :nothing more then gUessoe. NO reOOgniZcd #AT
Dopartacnt publications offered oven R thecreticnl solution to the problon;
they mcrcly stated tbJ nuoh requirements would vary under diiferenlj
circunstmcss. Realiaticnlly speaking, this memt thut coch erw
stc.ff had thc prerogativc of ~skingfor $.$hatit wanted. After the First
U.S. Amy nde its re+iromonts known in late 1943, a precedent HRS established
WhGch served as R guide for estimting and editing the requircments
of othar armies. 'phc mtter ~e.8never complstely aebpled
holwmr, end the division of service troops between the Bield Forcae
end the SOS continued to be a p int of difference throughout the OperAtion.
* See elso Stub Yo 9,1tService Troop Basle".