The Hawaiian Department, 7 December 1941


Summarizes historical information about the US Army in Hawaii on 7 December 1941.


The Army was proud of its preparations to defend Hawaii.  The Hawaiian Department was the Army's largest overseas department.  For more than three decades the War Department had constructed elaborate coastal defenses on Oahu.  The previous 18 months had seen the arrival of the Pacific Fleet, war scares, the start of selective service, numerous training exercises, the mobilization of the National Guard, and the doubling of the department's strength to 43,000 soldiers (including Air Corps).  The Hawaiian Department's two main tasks were to protect the Pacific Fleet from sabotage and defeat any invasion.  In April 1941 the Army Chief of Staff assured President Roosevelt:  "The Island of Oahu, due to its fortification, its garrison, and its physical characteristics, is believed to be the strongest fortress in the world."


The Hawaiian Department (Lt. Gen. Walter C. Short) had its headquarters at Fort Shafter with an underground command post at the Red Hill ordnance depot in the Aliamanu Crater.  The Hawaiian Coast Artillery Command (Maj. Gen. Henry T. Burgin) controlled a sophisticated system that guarded the sea approaches to Pearl Harbor and Honolulu Harbor.  Two infantry divisions were training at Schofield Barracks.  The Hawaiian Air Force (Maj. Gen. Frederick L. Martin) was ready to attack any hostile fleet.

Ground Combat Forces

On 1 October 1941 the Hawaiian Department reorganized its ground combat forces at Schofield Barracks into two infantry divisions, the 24th Division (Brig. Gen. Durward S. Wilson) and 25th Division (Brig. Gen. Maxwell Murray), each made up of two regular infantry regiments and one National Guard regiment, plus various support troops.  These units were being filled out with new selectees and were busy with basic and unit training and defense exercises.  In May 1941 the department deployed the 299th Infantry to the outer islands.  On the day of the attack, soldiers engaged attacking aircraft with small arms fire.  Units moved to their assigned defensive positions within hours, the 24th Division to the north shore and the 25th Division to Honolulu and the south shore.  The next day two soldiers of Japanese ancestry on guard at Bellows Field discovered a Japanese mini-submarine grounded on the reef and captured the surviving crewmember.  The feared amphibious invasion never came.

Coast Artillery

The Hawaiian Coast Artillery Command had its headquarters at Fort Ruger and four coast artillery regiments stationed at Fort Armstrong, Fort Barrette, Fort DeRussy, Diamond Head, Fort Kamehameha, Kuwaaohe Military Reservation (Fort Hase), and Fort Weaver.  These units played only a minor role during the attack.

Aircraft Warning and Antiaircraft Artillery

The department's four anti-aircraft regiments included fixed and mobile guns.  These included the 251st Coast Artillery (AA), California National Guard, sent to Hawaii in November 1940 and stationed at Camp Malakole (Honouliuli Military Reservation).  The Signal Corps had six SCR-270 mobile radar sets, but these were still experimental and had not yet been integrated into a functioning aircraft warning service.  On the day of the attack, the northernmost station at Opana picked up the inbound Japanese planes, but the temporary information center at Fort Shafter failed to recognize the significance of the report.  However some fixed antiaircraft units were able to engage the attacking aircraft.  One junior officer recalled, "We had gone so many times to our war positions that it just seemed like drill when they were firing at us." One air defense soldier, Cpl. Arthur A. Favreau, was killed at Fort Shafter by a stray Navy shell.  The Army later claimed to have brought down eleven Japanese aircraft by ground fire.

Internal Security

The Hawaiian Department had been concerned for years about the threat of sabotage by the large population of Japanese nationals in the event of a war with Japan.  The department shared intelligence with the naval district intelligence officer, the local FBI office, and territorial officials and was prepared to control civil disturbances under Emergency Plan White.  The G-2, Lt. Col. Kendall J. Fielder, quietly reached out to elements in the Japanese-American community.  Selective Service brought young Nisei men into the Army for the first time.  By December 1941 the department included about 2,000 Nisei soldiers, among them future US Senator Spark M. Matsunaga.  On the day of the attack, Lt. Gen. Short asked the territorial governor to declare martial law to head off any potential internal security problems.  After consulting with President Roosevelt by phone, the governor agreed.  Meanwhile, FBI and local law enforcement quickly seized Japanese consular officials and hundreds of community leaders and interned them on Sand Island.  On December 8 the Hawaiian Department staff judge advocate, Lt. Col. Thomas H. Green, moved into Iolani Palace to direct martial law operations.  The Territorial Guard, including hundreds of University of Hawaii ROTC cadets (many of them Nisei), sprang into action.  Soldiers and Territorial Guardsmen guarded military bases and critical facilities such as oil tanks and the water supply system.  The Army prohibited alcohol sales and imposed civil censorship.

Medical System

Civilian and military medical personnel worked miracles on the day of the attack and after.  The response was led by the Hawaiian Department chief surgeon, Col. Edgar King, MC, and was based on extensive pre-war civil-military planning.  Casualties from Hickam Field began arriving within ten minutes of the attack at Tripler General Hospital on Fort Shafter (the present Tripler Army Medical Center was not completed until 1948).  The Red Cross at once activated its local aid stations.  Future US Senator Daniel K. Inouye, then a senior at McKinley High School, was a Red Cross volunteer.

Civil Defense

The territory made significant preparations for civil defense in the year before the attack, with the encouragement of Army officials.  The legislature approved an emergency disaster plan in 1940.  Honolulu formed a Major Disaster Council in April 1941.  The council was especially successful in coordinating for civil-military medical cooperation and laid plans for blackouts, food rationing, and protection against chemical and biological attacks.  In October 1941 the legislature approved the Hawaii Defense Act, which granted the governor emergency powers and authorized a Territorial Guard to replace the already federalized National Guard.  During the attack Honolulu policemen and firemen responded to civilian casualties and destruction, much of it caused by errant naval gunfire from Pearl Harbor.  When the Hickam Field firefighting apparatus was knocked out, Honolulu fire companies responded and 3 civilian firemen were killed and 7 injured.

Army Casualties

The Hawaiian Department suffered far fewer casualties than the Navy or Marines.  In all, 228 soldiers were killed or died of wounds, 110 seriously wounded, and 358 slightly wounded.  Only 16 of the soldiers killed were not from the Air Corps.  From Schofield Barracks 5 soldiers were killed (only 2 by direct enemy action).  At Fort Shafter 1 soldier was killed accidentally by naval gunfire.  Ten soldiers were killed in other locations.

Commanding General

Lt. Gen. Walter C. Short took command of the Hawaiian Department in February 1941 and moved into Quarters 5, the commanding general's residence on Palm Circle.  On the morning of December 7 he was preparing for his regular Sunday morning golf match with his Navy counterpart, Adm. Husband E. Kimmel, when he heard heavy firing from the direction of Pearl Harbor.  He ordered his command to the highest alert and moved to his forward command post in Aliamanu Crater to direct the deployment of his command.  He was relieved on 17 December 1941 and retired shortly afterward.

  James C. McNaughton
  Command Historian

  20 November 2001



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