“From 1931 onward, Japan had been increasing aggressive in Asia. They had gone to war and taken over Manchuria, then they went to war openly with China in 1937, and (later) took over French IndoChina.” (Brown)
The threat of war was increasing. “By the late 1930s Schofield Barracks was the largest army base in the country, which is astonishing, and Pearl harbor was this huge naval base.” (Brown)
The Honolulu District of the US Army Corps of Engineers was involved with intense planning and vast preparations for what was an increasing possibility of a war in the Pacific. (Fitzgerald)
The possibility of a Japanese attack was real.
“Notwithstanding the seeming ‘normality’ of the prewar years, both military and civil authorities were taking steps to prepare for possible conflict”.
“Navy fleet exercises as early as 1938 simulated attacks on US defensive positions. On March 29, 1938, Hilo was the object of an exercise mounted by joint Army and Navy operations.”
“On May 23, 1940, the territory of Hawaii conducted its first island-wide ‘blackout’ requiring residences and business to shut off or shield their lights, cars to stay off the roads, and towns and cities to cut the power to streetlights.” (Chapman)
“Army Planes to Drop Leaflets On Blackout … Switching the entire territory into total darkness on the night of May 23 as part of maneuvers of the Hawaiian Department of the army is being prepared for on a wide as well as intensive scale. The smallest detail will not be spared to make this first territory-wide blackout a complete success.”
“For many weeks military officials have been working with the cooperation of civilian committeemen so that the blackout of the islands will be staged with the utmost precision and with the least possible inconvenience.”
“Army authorities announced that, in the effort to convey the information to all possible persons on all the islands, army planes will leave Hickam field on May 21 and shower the whole territory with blackout leaflets.”
“The message will be in English, Japanese, Chinese and Filipino and will serve as a reminder that cooperation of every one in the territory is imperative.”
“The ‘bombardment’ with blackout notices will be over Hawaii, Maui, Kauai, Molokai and Lanai. On Oahu, similar notices are being sent out through the mails and by house to house distribution.”
“Separated island residents will also receive these notices by mail. Planes will drop about 50,000 leaflets on out-islands. About 200,000 leaflets in all will be distributed.”
“Through the circulars the entire territory will be sent the message: ‘Blackout enemy planes will simulate attack on your island, Thursday night, May 23rd, 1940, sometime between 8:30 and 9 pm.’”
“‘When warning bells are rung or sirens are, sounded, IMMEDIATELY put out all lights, inside and outside. Turn off all signs. Don’t use flashlights, matches, etc. Blackout completely.”
“‘While the raid is only make-believes, do your part in this rehearsal for an event we hope will never come. Outblack the last blackout.’” (Nippu Jiji, May 8, 1940)
“The territory conducted a second island-wide blackout on May 20, 1941 … Yet another blackout exercise occurred on August 23.” (Chapman)
Then, it happened … Shortly before 8 am, December 7, 1941, Japanese aircraft from six aircraft carriers struck the Pacific Fleet as it lay in port at Pearl Harbor and other sites on O‘ahu.
According to plans developed over a decade earlier, martial law was imposed on Hawai‘i the same day of the bombing December 7, 1941. (Tanigawa)
“General Order 16 prescribed the painting of automobile headlights for night travel. It prescribed that the headlights be painted with black center and the tail lights be painted entirely blue.”
“The requirement that automobile headlights be painted might seem silly at a time when a war was going on but I can certify that it was a very serious matter. In operating a car in blackout it was imperative that each driver know which way the other was going.”
“Until it was satisfactorily regulated, it was like being blindfolded during a battle royal. It was next to impossible to proceed faster than a snail’s pace and even this was at great peril.”
“The color of the required painting was changed a number of times in an effort to satisfy drivers and also pedestrians. The latter complained bitterly that they had no protection against drivers who could not see them, and that they had to ‘run for it’ at all times and could not tell which way the automobile was moving.”
“On their side, the drivers complained that pedestrians loomed up in front of them at the most unexpected times and places. The lens color finally adopted was dull red which could be seen by drivers and pedestrians, if they concentrated on it and could not be seen by aircraft.” (Maj Gen Thomas H Green)
Beginning in July 1942 the powers of government were gradually restored to civilian authority, but some degree of martial law continued.
On February 8, 1943, power was restored to the Governor, the courts and the legislature. The commanding general proclaimed, “Full jurisdiction and authority are hereby relinquished by the Commanding General to the Governor and other officers of the Territory of Hawaiʻi”. (Anthony)