"I accordingly
applied my major efforts to the seizure of areas which were suitable
for airfields and base development, but which were only lightly
defended by the enemy."
-- General MacArthur,
in Reminiscences
[59]
In 1943, General
Douglas MacArthur's primary goal in the Southwest Pacific was to cut
off the major Japanese naval staging area, airfields and supply bases
at Rabaul. Located on the northeast coast of the island of New
Britain, Rabaul was the Japanese focal point for the protection and
reinforcement of the entire area. In order to seize this critical
target, it was first necessary to capture New Guinea, the strategic
right flank of the Japanese line of defense. The gulf port of Lae was
the final objective of the New Guinea offensive. In order to employ
all necessary forces for the assault, MacArthur needed an airfield in
the vicinity.
MacArthur's plan was
to "envelope them, incapacitate them, apply the 'hit 'em where they
ain't -- let them die on the vine' " method of "leap frog" advances.
As he explained to one of his staff officers, this was the very
opposite of the term "island hopping," which was the direct frontal
pressure against enemy-occupied islands in a long and costly effort.
Instead, he intended to envelop the enemy in order to bypass and
neutralize Japanese centers of strength. This maneuver required the
careful selection of key points, usually lightly defended areas that
were suitable for airfields and bases, as objectives. The timing of
their seizure was critical for success.[60]
The lack of aircraft
carriers and naval aviation significantly hampered MacArthur's
progress in the Southwest Pacific. The very nature of "leap frogging"
depended on achieving air superiority over each move forward. The
limit of advance in the Southwest Pacific was the maximum range of
ground-based fighter aircraft. The presence of aircraft carriers
would have enabled MacArthur to strike quickly and decisively
throughout the entire area of operations, but reliance on ground-based
aircraft meant that he had to advance airbases to support each
subsequent operation.[61]
The senior
intelligence officer of the Japanese Eighth Area Army described
MacArthur's successful strategy to secure Buna, Papua:
This was the type of
strategy that we hated most. The Americans, with minimum losses,
attacked and seized a relatively weak area, constructed airfields and
then proceeded to cut the supply lines to troops in that area.
Without engaging in a large-scale operation, our strongpoints were
gradually starved out. The Japanese preferred direct assault after
the German fashion, but the Americans flowed into our weaker points
and submerged us, just as water seeks the weakest entry to sink a
ship. We respected this type of strategy for its brilliance because
it gained the most while losing the least.[62]
This strategy worked
to capture Buna, so MacArthur planned to use it again to take Rabaul.
With the fall of
Papua in January 1943, the Japanese consolidated their defensive
positions. They withdrew along the northern coast of New Guinea, New
Britain and the northern Solomons. New Guinea was the strategic right
flank of the Japanese line of defense. From New Guinea, the Allies
were able to begin operations into the heart of the Japanese-occupied
areas, and eventually assault the Philippines and Japan itself.
Final planning for
the Rabaul operations began after the U.S. Joint Chiefs of Staff
issued their planning directive on March 28, 1943. The directive
ordered General MacArthur and Admiral William F. Halsey, commander of
the South Pacific Area (SOPAC), to accomplish the following tasks:
establish airfields on Woodlark and Kiriwina Islands; seize the
Lae-Salamaua-Finschhafen-Madang area of New Guinea; occupy western New
Britain; seize and occupy the Solomon Islands as far as southern
Bougainville.[63]
MacArthur commanded the entire operation, but the advances in the
Solomons were under the direction of Admiral Halsey (see fig. 2).
SOPAC was one of the three subordinate commands of Admiral Chester W.
Nimitz's Pacific Ocean Area. Except for the forces designated for the
Rabaul operations, Halsey remained under Nimitz�s control. This
arrangement was another one of the complicated chain of commands in
the Pacific Theater. Fortunately for the Rabaul operation, the
violation of the principle of unity of command did not affect the
outcome.[64]
The planning task to
seize Rabaul was not difficult because MacArthur's Southwest Pacific
Area (SWPA) General Headquarters (GHQ) had already developed two
previous plans (designated ELKTON) to accomplish this mission. On
April 26, 1943, SWPA GHQ issued its plan, codenamed ELKTON III, after
a personal conference in Brisbaine between Halsey and MacArthur. The
joint operations of the SWPA and SOPAC would occur under the codename
CARTWHEEL (see fig. 3). The plan, calling for mutually supporting
advances along two axes of SWPA and SOPAC forces, envisioned thirteen
amphibious operations, over eight months, culminating in the capture
of Rabaul.[65]
The SWPA and SOPAC
plans each had three phases. The SWPA phases were I, II and III and
the SOPAC phases were A, B and C (see figs. 4 and 5). The initial two
phases (Operation I and A) began simultaneously. Operation I was the
seizure of Woodlark and Kiriwina and Operation A was the ground
operations in the Solomon Islands (New Georgia and Santa Isabel).
Operation II was the capture of Lae (IIa), Salamaua and Finschhafen
(IIb), and Madang (IIc). One month later, the SWPA would begin
Operation B to complete the conquest of New Georgia and move forward
to take the Japanese bases on the Shortland Islands and Buin in
southern Bouganville. The final set of operations would also begin
simultaneously. Operation III would cross the Vitiaz Strait to seize
Cape Gloucester and Operation C would take control of Buka Island
before converging on the final objective of Rabaul.[66]
MacArthur used mainly
the existing headquarters in his command to execute ELKTON III (see
fig. 6). But he did set up, under the direct control of his GHQ, a
new, primarily American, task force (Alamo), under the command of
Lieutenant General Walter Krueger. The Alamo force was virtually the
same as the Sixth Army that Krueger commanded. The remainder of the
ground forces, primarily Australian, was the New Guinea Force, under
the control of Australian General Sir Thomas Blamey. The Alamo Force
conducted operations in Woodlark, Kiriwina and New Britain while the
New Guinea Force fought primarily in New Guinea. Lieutenant General
George C. Kenney, commander of the U.S. Fifth Air Force, was
responsible for the Allied Air Forces.[67]
Vasey was
also unsatisfied with the plan for one parachute battalion to seize
the airstrip against possible opposition, while also preparing the
airstrip for the transport planes to bring in the 7th
Australian Division. Enemy movement down the Markham Valley was
increasing and it was essential to seize the airstrip quickly.
Although the Japanese did not occupy it, patrols passed through the
area on a regular basis. On July 31, Vasey discussed with Colonel
Kenneth H. Kinsler, Commander of the 503d PIR, the
possibility of using the entire regiment for the assault. Kinsler
"jumped" at the chance. On August 2, Vasey wrote to Herring
requesting the use of the entire 503d PIR in the
operation. Since it was a theater asset, the approval of MacArthur's
GHQ was necessary; that obtained, planning for the operation
continued.[78]
There was
another plan developed that called for an Australian infantry brigade
to fly into Tsili-Tsili several days before the operations at Nadzab
and then move down the Watut River to the Markham River to be in
position to support the airborne operation and seizure of the airstrip
at Nadzab. As the planning continued, Vasey reduced the force to just
the 2/2nd Pioneer Battalion and the 2/6th Field
Company. After the 503d PIR seized the airstrip, the
pioneers and engineers would prepare the airstrip for the 7th
Australian Division's air-movement.[79]