Over the beach - University of Oregon

the Pacifc. 46 Beginning in the early 1920s, the Joint Board also developed
a plan for operations against Japan fghting alone (Joint Basic War Plan
Orange). This plan originally envisioned operations across the Pacifc to
transport an Army expeditionary force to rescue the Philippines. While all
the variations of the Orange Plan called for the Navy to fght its way across
the Pacifc, capturing Japanese-held island bases en route, the Army’s role
in the Philippines varied from reinforcement, to holding out with the forces
available, to abandonment. The last version of the plan before World War
II began was approved in 1938. Under this plan, the Army would reinforce
Alaska with 7,000 troops, Hawaii with 25,000 troops, and the Panama
Canal Zone with 15,000 troops. Neither the Philippines nor Guam would
receive reinforcements. Guam was undefended in accordance with the
Washington Treaties and was expected to fall quickly. The Army would
hold out in the Philippines with the forces available as long as possible. 47
The third area of Joint Board deliberations relevant to amphibious
operations was the publication of guidance for expeditionary warfare. The
Army and Navy had conducted joint maneuvers in Hawaii in 1925 that
included a landing by two battalions of marines. 48 In 1929 the Joint Board
published Joint Overseas Expeditions—Tentative. Revised and reissued in
1933 as Joint Overseas Expeditions, this document addressed cooperation
between the Services and the functions of each during joint landing operations.
It provided broad guidance on the organization of landing forces
into battalion combat teams, the functions of Navy beach masters and
Army shore parties, commercial versus combat loading of transports, the
necessity of Army and Navy commanders to be aboard the same ship, and
the selection of beaches. It also addressed the advantages and disadvantages
of day and night landings: better control of landing craft and troops,
better air and naval fre support coordination, and better defense against
hostile air and naval units in the case of the former; increased chance of
tactical surprise and reduced effcacy of the defenders’ fres in the case of
the latter. However, it did not provide specifc guidance on the tactics and
techniques of landing on a defended beach—a subject the Marines would
take as their special mission. 49
Marine Corps Developments
Major General John A. Lejeune, who became commandant of the
Marine Corps in 1920, put particular emphasis on the advance base force
mission. Under his direction, a group of staff offcers headed by Major
Earl H. Ellis produced a detailed study of the requirements for “Advanced
Base Operations in Micronesia.” Approved in July 1921, it served as the
basis for Marine Corps planning, mobilization, and training. 50 In 1922
22