Cassino to the Alps - US Army Center Of Military History

454
forces still in northwest Italy. In cooperation
with the Eighth Army's drive
to the northeast, the II Corps was to
cross the Po and advance to the Adige.
Meanwhile, the 92d Division on the
army's left flank, operating directly under
the Fifth Army, was to continue its
advance along the Ligurian coast to
Genoa, Italy's major seaport, and
thence northwestward to an eventual
link-up with French forces along the
Franco-Italian frontier. 31
The Fifth Army's Operation BIG
GAME was designed to create the illusion
that the I I Corps was moving
eastward to join the Eighth Army in
making the main Allied effort along the
Adriatic flank and that the IV Corps
would take over the Fifth Army's entire
front. Dummy radio nets were established
for some units, and radio silence
imposed upon others. While most of
the movement was simulated, some
units, their divisional markings removed
from personnel and equipment, actually
shifted but only within the army sector.
32
To avoid having to divide air support
equally between the two armies, Clark
instructed Truscott to delay his phase
of the offensive until about D plus 3
when the Eighth Army would have
crossed the Santerno River. Thus the
full weight of the tactical and strategic
air forces could be thrown in support
first of the Eighth Army on the right,
then of the Fifth Army on the left.
Truscott developed a similar scheme
for allotting air support between his two
corps. Attacking first, Crittenberger's
31 Hq, U.S. Fifth Army, Opns lnstr. No.7, I Apr
45, in Fifth Army History, Part IX, ann. E.; Truscott,
Command Decisions, pp. 478-79.
32 Ibid., IX, 26.
CASSINO TO THE ALPS
IV Corps would at first receive the
Fifth Army's entire allotment of airpower,
then 36 hours later all air
support was to be shifted to su pport of
Keyes' 11 Corps. Staggering the army's
attack in that manner also had the
advantage of placing greater firepower
alternately behind each of the two army
corps rather than dividing it between
them as McCreery had done with the
Eighth Army. While assigning one of
the Fifth Army's two armored divisions
to each corps, Truscott nevertheless
managed to assure a concentrated armored
thrust by positioning both divisions
side by side on the interior wings
of the corps: the U.S. 1st Armored
Division on the I V Corps' right and the
South African 6th Armoured on the II
Corps' left. :!;;
Within the Fifth Army's· main wne of
operations opposite the IV and I I
Corps only two highways, 64 and 65,
led through the 12-mile belt of remaining
mountainous terrain between the
front and the Po Valley. Long favored
by Clark, Highway 65 offered the most
direct approach. Except for two rugged
peaks, Monte Sole and Monte Adone,
rising above north-south running ridge
lines bordering the Setta valley between
Highway 65 and the Reno River to the
west, the terrain was favorable and
permitted movement and support of up
to five divisions. The main disadvantage
of Highway 65 lay in that the Germans
had concentrated their strongest positions
astride it in defense of the southern
approaches to Bologna. A major
offensive along that route might involve
330pns Instr. No.7, I Apr 45, Hq Fifth Army,
in Fifth Army History, Part IX, ann. E. Unless
otherwise indicated the following sections are based
upon this source.