In 1920 the new Marine Corps Schools at Quantico became the center of Marine amphibious study and research. Marine units participated in fleet problems at Panama and Culebra during the post-war years; and in 1927 the Joint Board of the Army and Navy (forerunner of JCS) stated in a directive that the Marine Corps had the mission of “special preparation in the conduct of landing operations.”[75] [75] BrigGen Eli K. Cole, “Joint Overseas Operation,” _US Naval Institute Proceedings_, 55, No. 11 (Nov 29):927. During the early 1920s the writings of a brilliant Marine officer, Major Earl H. Ellis, had a tremendous influence on current amphibious thought. Predicting that Japan would strike first in the Pacific and win initial successes, he drew up a strategic plan for assaults on Japanese-mandated islands which was approved by Major General John A. Lejeune, Commandant of the Marine Corps. Later known as Operation Plan No. 712, this Top Secret document helped to shape the ORANGE plans adopted by the Joint Board of the Army and Navy for offensive operations against Japan if it came to war. After making good progress in the early 1920s, with landing exercises being held annually, the Marine amphibious program bogged down from 1927 to 1932 because of the necessity of sending expeditionary forces to China and Nicaragua. The turning point came in 1933, a memorable date in the evolution of modern amphibious warfare. It was then that Major General John H. Russell, Assistant Commandant of the Marine Corps, urged that a staff be set up at Quantico to plan for the organization of a mobile Marine striking force. This force, under the Commandant, and fully prepared for service with the fleet, was to be in readiness for tactical employment subject to the orders of the Commander in Chief, U. S. Navy. General Russell further proposed that the old name “Expeditionary Force” be discontinued and “Fleet Marine Force” adopted as a name better expressing this mission.[76] [76] J. A. Isely and P. A. Crowl, _The U. S. Marines and Amphibious War_ (Princeton, 1951), 21–24, 33–34. After the acceptance of these recommendations, the Commandant ordered classes discontinued at the Marine Corps Schools and a concerted effort applied to the preparation of a new amphibious manual. Both the Army and Navy had treated some of the procedures in existing manuals, but it remained for the Marine Corps in 1934 to put out the first complete work of the sort. Known as the _Tentative Manual on Landing Operations_, it became either directly or indirectly the guide for exercises and maneuvers of the Navy and Marine Corps down to World War II. Most of its suggested procedures were endorsed with revisions in the Navy’s _Fleet Training Publication 167_, published in 1938. This work in its turn became the model three years later for the Army’s first basic field manual for landing operations.[77] [77] FMFPac, _History_, 6–9.