Japanese Preparation and Attack on Pearl Harbor During the early part of the 20th century, Japan was faced with some fundamental challenges in its effort to expand its empire throughout Asia and beyond. Although Japan had enjoyed some significant successes during the first decades of the 20th century, including the colonization of the Korean peninsula and military successes in China and Indo-China, the United States stood poised on the other side of the Pacific as a formidable bulwark of democracy with its naval forces stationed at Pearl Harbor representing a geographic thorn in Japan's side. Following its alliance with the Axis powers in World War II, Japan was faced with the need to counter this potential threat to its expansionist plans as well as America's efforts to restrict its access to badly needed resources through a preemptive air strike on Pearl Harbor and ancillary facilities. In reality, though, beyond the Neutrality Act passed by the U.S. Congress in 1935 that prohibited arms sales to countries that were at war, America was still gripped by a lingering economic downturn as well as by a sense of isolationism that kept domestic attention focused primarily on domestic issues to the exclusion of what was taking place in Japan and Europe.

In this regard, Divine notes that during the 1930s, the prevailing view "was a policy of continentalism, claiming that what happened abroad was of little consequence to a United States whose mission was to perfect democracy at home."

The Japanese attack on American forces stationed at Pearl Harbor located in Hawaii on December 7, 1941, though, would change all of this in fundamental ways as discussed further below.

Review of the Strategic Setting

The overarching immediate goal of the Japanese attack on Pearl Harbor in 1941 was to disable the United States' Pacific fleet, particularly its aircraft carriers, to the maximum extent possible, thereby allowing Japan the opportunity to consolidate its forces in the region and provide it access to sorely needed resources in China as well as throughout Asia.

For instance, according to Nish, "The focus of Japan's policy in this period was predominantly continental, that is, securing her objectives in China and later in Southeast Asia."

This goal is understandable, perhaps, given the perception by the Japanese military and, to a lesser extent, political leadership that the United States was further threatening its access to the resources it would need to achieve its expansionist goals throughout Asia. For instance, according to Wirtz, "Prior to Pearl Harbor, U.S.-Japanese relations had reached a nadir. By the summer of 1941, the administration of U.S. President Franklin Roosevelt had placed economic sanctions on the Japanese to force them to end their war against China. These sanctions were the proximate cause of the Japanese attack."

Even though Japan gained a short-term tactical advantage in its theatre of operations, the true significance of the attack was America's declaration of war on Japan and the solidification of American resolve to avenge the attack at any cost, a strategic failure that is discussed further below.

Opposing Forces -- Japan

The order of battle for the attack on Pearl Harbor is provided at Appendix A. In sum, the Japanese suffered the loss of just 55 crewmen plus nine men killed and one captured on minisubmarines; by contrast, American Navy casualties numbered 2,008 (killed, missing or died of wounds) and 710 wounded, 109 Marines killed and another 69 wounded, 218 Army and Air Corps members killed, missing or died of wounds and another 364 wounded and over a hundred civilian casualties, as well as the warship casualties described in Table 1 below.

Table 1

US Warship Casualties at Pearl Harbor

Status

Description

Sunk, not repaired

Arizona (battleship)

Oklahoma (battleship)

Utah (target ship)

None of these ships has been restored (Oklahoma was sold for scrap in 1944 but was subsequently lost in 1947 on its way to the boneyard and portions of the other two remain at Pearl Harbor today).

Destroyed but rebuilt

Cassin (destroyer)

Downes (destroyer)

These two destroyers were very badly damaged and were decommissioned after the attack; however, much of their machinery and other items were determined to be salvagable and so were installed in new hulls. These ships carried the same names and hull numbers but they were essentially new construction.

Sunk or beached but later salvaged

West Virginia (battleship)

California (battleship)

Nevada (battleship)

Oglala (mine layer)

Damaged

Tennessee (battleship)

Maryland (battleship)

Pennsylvania (battleship)

Helena (light cruiser)

Honolulu (light cruiser)

Raleigh (light cruiser)

Shaw (destroyer)

Curtiss (seaplane tender)

Vestal (repair ship)

Source: Czarnecki, Worth, Noch, Horan & DiGiulian, 2011

Besides the foregoing naval losses, the United States also...

Naval General Staff -- Admiral Nagano Osami. An experienced naval officer with substantial political experience, Admiral Osami emphasized the need to attack Pearl Harbor because the Americans had left the Japanese "no choice left but to break the iron fetters strangling Japan" in response to America's freezing of Japanese assets.
Combined Fleet. Admiral Yamamoto Isoroku. This naval officer preferred a more aggressive campaign against the Allied Pacific forces, including a follow-up invasion of Australia, but was opposed by the army.

Described by Rimer as "one of the great heroes of the war,"

Admiral Isoroku was killed in 1942 when his plane was shot down over the Bougainville Islands.

First Air Fleet and First Carrier Division. Vice Admiral Nagumo Chuichi. Described by Tsuzuki as the "commander of the mobile fleet which brilliantly attacked Pearl Harbor,"

Vice Admiral Chuichi had extensive experience in commanding the Central Pacific Fleet headquartered at Truk prior to the Japanese attack on Pearl Harbor.

The personalities of each of these Japanese military leaders were reflective of the bushido ethic that dominated the Japanese military preparatory to and during the prosecution of the war.

These Japanese commanders were faced by U.S. Chief of Naval Operations Admiral Harold R. "Betty" Stark and the Commander in Chief, U.S. Fleet, Admiral Husband E. "Mustapha" Kimmel.

A complete listing of the military equipment and forces array against the Americans at Pearl Harbor is also set forth at Appendix A.

The Campaign/Battle

The Japanese battle plan for Pearl Harbor involved two attack waves that employed 360 aircraft in total (189 for the first wave and 171 for the second wave).

In addition, scout planes were used to gather intelligence preparatory to the aerial strike, with a total of 405 Japanese aircraft being deployed during the battle.

The instructions provided to the Japanese forces in command memorandum No. 97 included the orders shown in Table 2 below.

Table 2

Japanese Battle Plan for Pearl Harbor as Set Forth in Memorandum No. 97

Area of Responsibility

Battle Plan Orders

The First Wave

The fighter-bombers and torpedo-bombers will attack the battleships and then the aircraft carriers. The dive-bombers should attack ground targets. The aircraft from Shokaku are to attack the airfield at Ford Island with all its installations, the other aircraft, Wheeler airfield and its installations. The fighters are to be used as CAP over the U.S. airfields.

The Second Wave

The fighter-bombers from the Shokaku are ordered to attack the airfield on Kaneohe and Ford Island. The aircraft from the Zuikaku are assigned to Hickam Field. The dive-bombers should attack the aircraft carriers, if the carriers are absent, they should attack other capital ships. The fighters are to be used as CAP over the U.S. airfields.

Route of Attack

The decisive strike belonged to the first wave. The torpedo-bombers should spearhead the attack as they were the most vulnerable and so needed the moment of surprise the most. The fighters were ordered to fly CAP and destroy all enemy fighters, on the ground if possible. The fighters from the Kaga and Akagi were to patrol over Hickham Field and Barbers Point, the fighters from the Soryu and Hiryu over Wheeler and Barbers Point and those from Shokaku and Zuikaku over Kaneohe.

Source: Czarnecki et al., 2011, 5

Significance of Attack on Pearl Harbor

Short-term significance. Besides serving as the focal point that catalyzed American resolve to avenge the attack, the Japanese attack on Pearl Harbor resulted in the almost immediate internment of more than a hundred thousand Japanese-Americans and Japanese immigrants living in the United States. According to Flamiano, "After the Japanese Navy attacked Pearl Harbor on December 7, 1941, the United States entered World War II and anti-Japanese hysteria gripped the home front. Then, on February 19, 1942, President Franklin D. Roosevelt signed Executive Order 9066 authorizing the War Department to exclude any group of people from military areas for the duration of the war."

Moreover, the Japanese attack on Pearl Harbor also yanked Americans from their isolationist cocoon and galvanized public opinion that war was the only viable response. In this regard, Hill emphasizes that, "[Pearl Harbor] convinced a majority of Americans to escalate to total war against Germany; most Americans believed that Germany was either an accomplice or the political master of Japan, thus making Hitler at least as guilty as Japan for the attack on Pearl Harbor. The attack on Pearl Harbor was the defining event for U.S. entrance…