Missing Pieces: - Royal Australian Navy

74 Missing Pieces
went to the former. Even MacArthur had to fight hard to have US Army and USAAF
resources assigned to his command.
When Nimitz succeeded to the Pacific Command in the wake of Pearl Harbor, he and
his staff were strongly inclined to keep the fleet’s strike forces — its carriers — as a
mobile shield between Hawaii and the Japanese. Admiral King would have none of this,
and directed offensive action. When Rear Admiral Crace paid a visit to USS Chicago,
part of his ANZAC Force, on 13 February 1942, he was given a copy of a message from
King to Vice Admiral Leary telling him to ‘hoist his flag and proceed to aggressive
measures in New Britain and the Solomons’.
On the Japanese side, their war strategy saw the conquest of the Philippines, Malaya
and NEI as its First Operational Stage, which had been forecast to take five months.
The Second Operational Stage, with not so well developed plans attached, involved
establishing a new defensive perimeter for the East Asia Co-Prosperity Sphere. This
would stretch from Port Moresby, through New Caledonia, Tulagi in the Solomons, Fiji
and Samoa, and then to Midway and the Aleutians. 207 From Port Moresby, Japanese
air power would deny the Allies the use of the north of the Australian continent as a
springboard for a counterattack. Japanese bases in the southern island groups would
control the intervening seas and interdict communications between the United States
and Australia. 208 Possession of Midway would bring Hawaii under Japanese attack and
compel the US Pacific Fleet to keep its day of destiny in the ‘decisive battle’ sought
by IJN strategists.
Japanese Imperial Headquarters initiated Stage Two for the IJN on 23 January 1942
as Naval Directive 47. In fact, the Japanese were in considerable difficulty when
confronting the reality of defending an empire covering some 200,000 square miles.
This problem seems not to have been thought through in the hothouse atmosphere
that led to the first-stage attacks, and the Japanese belief appears to have been that
they could negotiate an end to the war by waging a defensive campaign inside their
newly expanded imperial perimeter to sap the will of the Allies. Nevertheless, the IJN
developed the means to accomplish most of these objectives in two operational plans.
Operation AF covered Midway and the Aleutians, while MO covered Port Moresby,
Tulagi and the occupation of Ocean Island and Nauru. As Operation AF was scheduled
for early June 1942, Operation MO was planned to take place in early May to allow
time for the forces involved to rejoin the Combined Fleet for the anticipated ‘decisive
battle’ off Midway.
Nimitz in Hawaii was being advised by his cryptanalysts of indications of plans for
attacks in both regions, JN-25B having been penetrated in December 1941. This gave
the Allies time to prepare and assemble forces to deal with the threat. While the counter
to Operation MO would be principally naval in character, the battle was expected be
fought in the sea areas of SWPA. Nimitz would, under CCS directive, control the naval
forces but these would need to be supported by MacArthur’s land-based air resources.