Defenses of Pearl Harbor & Oahu 1907-50

Rating:
Summary: The Dinosaurs of Oahu
Review: Osprey's Fortress #8, Defenses of Pearl Harbor & Oahu 1907-1950 by Glen Williford and Terrence McGovern, is an excellent summary of the extensive American efforts to fortify the Hawaiian Islands during the first half of the 20th Century. This volume is also markedly superior to the authors' previous volume on US defenses in the Philippines (which lacked details on costs or duration of fortification development). For those readers interested in the Japanese attack on Pearl Harbor in December 1941, this thin volume can add a great deal about the extent of American defensive preparations. This volume is also very useful as a case study on the long-term efficacy of a specific US defense policy (i.e. was the expense worthwhile?).

Defenses of Pearl Harbor & Oahu 1907-1950 begins with a short introduction on the American acquisition of Hawaii in 1898 and a chronology of US military activities in the islands. Short sections follow on the initial plans for the defense of Oahu, building the main defenses in 1915-1925, garrison life on Oahu, defense modifications between the wars, Hawaii during the Second World War, and postwar changes. The final sections comprise a short assessment, notes on the sites today, a bibliography and two appendices (characteristics of US coastal artillery and a list of all fixed coastal batteries on Oahu). The volume also has three maps (Pacific overview, Oahu geography, Oahu south seacoast defenses) and eight color plates (Leahi Peak fire control complex, Fort Ruger in 1916, Fort Kamehameha in 1921, Battery Harlow in mid-1930s, range of Oahu defenses in 1941, casemating Battery Hatch in 1942, Battery Arizona, coastal battery range fans in 1940s). The supporting photographs are also quite good. The only shortcoming in the volume is that the authors are overly-focused on fixed coastal defenses and skimp on details of mobile forces such as aircraft or ground units - for example, they should have listed the aircraft available to the Hawaiian Air Force in December 1941 (after all, at least a few P-40 fighters participated in the defense of Pearl Harbor, unlike the coastal batteries).

Beginning in 1907 - before there was even a significant Japanese threat to Hawaii - the United States embarked upon a major effort to develop a system of coastal fortifications and batteries to protect the incipient naval facility at Pearl Harbor. Interestingly, the US Army developed the coastal defenses for Pearl Harbor much faster than the US Navy developed the port itself (which required extensive dredging and base construction), and the US Pacific Fleet did not even homeport major units in Hawaii until 1939. Nonetheless, Williford and McGovern note that, "between 1907 and 1938, the Army had spent about $150 million on the defenses of Oahu - twice as much as was spent on the naval base itself." For a cash-strapped US military, this was a huge, sustained investment (the US defense budget in the 1930s was $700-800 million per year).

The authors also do a wonderful job detailing the battery construction effort, which on paper provided Pearl Harbor with very formidable defenses against seaborne attack by 1920. However, both the early defenses and those added in the interwar period paid little heed to the possibility of air attack; most of the batteries were sited out in the open, completely exposed to air attack or overhead shell bursts. Although the US Army had 60 anti-aircraft guns in Hawaii by 1941, they were obsolescent types lacking modern fire control. It was not until September 1940 that the US began adding overhead protection to some of the smaller batteries, but all the big 12", 14" and 16" guns in Hawaii were open-air mounts on December 7, 1941. If the Japanese had intended to follow-up the Pearl Harbor raid with an invasion, these large coastal guns would have been easy meat for Japanese "Val" dive-bombers.

Did the millions invested in the fixed defenses of Hawaii pay-off when attack did come in December 1941? Of course not. Indeed, the authors are too kind in suggesting that some US Army AA guns participated in the final moments of the Japanese attack (expert Gordon Prange said they did not) and they overlook Major General Walter Short's dumb decision to leave all AA guns and ammunition locked up to prevent sabotage. In fact, none of the fixed defenses of Oahu fired a shot against the Japanese attack that devastated the US Pacific Fleet at anchor and thus, the defenses completely failed in their mission. It is also odd that after the Pearl Harbor attack, the US redoubled its fortification efforts on Oahu and continued to add more batteries right up to the end of the war. The most ambitious project was the salvaging of two triple 14" gun turrets from the sunken USS Arizona and then mounted on coastal batteries; the first turret was operational in August 1945. Given the overwhelming nature of US airpower by 1944, it is amazing that money and resources were still being poured into obvious dinosaur projects like coastal batteries. There is a lesson in these pages about inertia in defense spending that might be useful for modern readers to consider.

The final question this book arises is about "opportunity cost." If the US had not lavished so much funds on highly vulnerable and fixed fortifications, more money would have been available to the cash-starved US military of the 1930s to develop mobile weapons. On one page, the authors provide a photograph of obsolete B-18 "Bolo" bombers on Hickam Field in the 1930s - the aircraft that comprised the bulk of the US bomber force on Oahu in December 1941. The $150 million spent on fortifications could have been spent on improving US aircraft before the war, or buying more search planes. Indeed, the fortifications on Oahu should provide a salutary lesson on the dangers of over-investing in legacy technology designed for only limited applications.

Rating:
Summary: Superb Study
Review: This is the best volume so far of the Osprey Fortress Series.
It was written by two long time members of the Coast Defense Study Group, the preminent organization dedicated to the history and preservation of US Coast Defense Installations. The book is crammed full of details and facts, and is accompanied by beautiful drawings, plans, maps and photos. This book is a perfect example of how histories of fortification should be written.