Battles & Wars › World War II › Attack on Pearl Harbor
Mitsubishi: the Zero fighter and battleship Musashi
Zero first flew April 1, 1939; Musashi launched 1940· Arms maker, factory or program· Arms makers & war industry
Well documentedSolid records, physical evidence or scientific consensus.
Japanese industrial group that built the Zero fighter, the giant battleship Musashi and much of Japan's wartime arsenal.
See it on the Battles & Wars map →What happened
Founded as a shipping firm in 1870, Mitsubishi grew into a zaibatsu, a family-controlled conglomerate. Designer Jiro Horikoshi's A6M Zero, first flown April 1, 1939, won long range and agility by saving weight, at the cost of armor and self-sealing fuel tanks. About 10,900 were built, by Mitsubishi and, in larger numbers, Nakajima. Mitsubishi's Nagasaki yard secretly launched the battleship Musashi in November 1940. Its plants also made engines, tanks and torpedoes, using conscripted Korean and Chinese workers and Allied prisoners.
Why it matters
The Zero ruled Pacific skies in 1941–42 until US pilots learned tactics against it and better US fighters arrived; Musashi's sinking showed aircraft had eclipsed battleships.
How we know
Japanese navy and company records, US Strategic Bombing Survey reports, Horikoshi's memoir, and Musashi's wreck, found in 2015 in the Sibuyan Sea. Wartime forced labor is documented in court records.
Still debated
Compensation for Korean forced laborers remains disputed: South Korea's Supreme Court ordered Mitsubishi Heavy Industries to pay in 2018; Japan says a 1965 treaty settled all claims.
Connections (4)
▸Grumman and the F6F Hellcat outfought the Zero fighters of Mitsubishi: the Zero fighter and battleship MusashiMostly agreed
The connection
Mitsubishi's A6M Zero was nimble and long-ranged but light, with little armor. The Hellcat was faster in a dive, better protected and heavily armed. With better-trained pilots and tactics, Hellcats overwhelmed Zeros by 1944, notably in the 'Great Marianas Turkey Shoot' of June 1944.
When and how
Pacific theater, 1943–1945; peak at the Battle of the Philippine Sea, June 19–20, 1944, where Japan lost hundreds of aircraft.
How sure are we?
US and Japanese loss records; US kill claims are known to be inflated, but Japanese losses were confirmed as very heavy.
Debates and open questions
A popular story says the Hellcat was designed from a captured 'Akutan Zero,' but its design was largely set before that plane was studied.
▸Mitsubishi: the Zero fighter and battleship Musashi built the Zero fighters that escorted the Attack on Pearl HarborWell documented
The connection
Of about 350 Japanese planes in the two attack waves, 78 were Mitsubishi A6M Zeros, which guarded the bombers and strafed US airfields to destroy planes on the ground. The Zero's long range also let Japan hit the Philippines from Taiwan the same day.
When and how
Oahu, December 7, 1941; Zeros from the six carriers of Admiral Chuichi Nagumo's strike force.
How we know
Japanese and US after-action records and the attack plans list the aircraft types and numbers.
Debates and open questions
US officials had reports of the Zero's performance from China in 1940–41, including from Claire Chennault, but largely ignored them; why is discussed.
▸Mitsubishi: the Zero fighter and battleship Musashi built the battleship Musashi, sunk at Battle of Leyte GulfWell documented
The connection
Musashi and her sister Yamato were the largest battleships ever built, with 46 cm guns. Musashi was built at Mitsubishi's Nagasaki yard. At Leyte Gulf, on October 24, 1944, US carrier planes hit her with an estimated 17–19 torpedoes and some 17 bombs in the Sibuyan Sea, and she sank; over 1,000 of her crew died.
When and how
Sibuyan Sea, the Philippines, October 24, 1944; aircraft from US Task Force 38 under Admiral William Halsey.
How we know
US and Japanese action reports; the wreck, found in 2015 at about 1,000 m depth, shows the damage.
Debates and open questions
Hit counts vary between US claims and survivors' accounts; how long she stayed afloat under such punishment surprised both sides.
▸Mitsubishi: the Zero fighter and battleship Musashi saw its Nagasaki arms plants destroyed in the Atomic bombings of Hiroshima and NagasakiWell documented
The connection
Nagasaki was largely a Mitsubishi city: its shipyard, steel works, arms factory and torpedo plant employed tens of thousands. The bomb of August 9, 1945, exploded over the Urakami valley between the steel and arms works and the torpedo plant, destroying both. Many of those killed were Mitsubishi workers, including conscripted Korean laborers.
When and how
Nagasaki, August 9, 1945; the US B-29 Bockscar dropped the plutonium bomb 'Fat Man'.
How we know
US Strategic Bombing Survey reports, Japanese damage surveys and survivors' accounts document the plants' destruction.
Debates and open questions
Kokura was the first-choice target until clouds diverted the plane to Nagasaki; how many Korean workers died there is still uncertain.