“It is not only an American story, but also a World war II story,” says Tom Kochel, a senior lecturer in history at the University of Oxford.
“This is a story of what could have been.
In this war, the Japanese came and attacked, and the Americans came and stayed.”
Genshins were a special kind of artillery gun that was meant to blast holes in enemy defences to help relieve pressure on enemy positions.
A Japanese attack was almost immediately followed by a surprise attack by the Americans, and Genshitons were used to inflict heavy damage on the enemy.
It was one of the main weapons of World War Two, but was used by the Japanese as well as the British.
“In this war,” says Kocher, “the Genshunin and the American artillery are the two main weapons used by Japan, and that’s a big reason why they are the greatest enemies of the United States.”
Aerial view of Genshi, New York, August 12, 1945.
Koche says the Genshains had a range of 5-20 kilometres, and were powerful enough to destroy artillery batteries or small ships, and they could penetrate enemy armour.
In the Japanese siege of Gendai, a small town in central Japan in August 1945, the Gensen were used for breaching the defences of the Japanese army and, according to a memoir by Major Kiyoshi Kawamura, an American officer, had been used to blast an enemy hole.
A Genshouin was also used by British forces during the Burma campaign in World War I. Kuchel says that during World War 2, the number of Gensen used by Allied forces was extremely limited, with just over 300,000 being used in the Pacific alone.
A small section of the G-class Genshein artillery gun was used in Burma in 1942, but the gun was later scrapped.
The Genshai were one of several Japanese forces that were used in World Wars 2, including the Japanese Imperial Army, the Soviet Union, and China.
“It’s quite clear from the evidence that they were used by a small number of people,” says Michael Sacks, an historian at Australia’s Griffith University.
“They were not necessarily the only ones.”
Koches research into Genshig was published in the journal The Lad in 2014, and has been featured on the BBC World Service’s podcast The Lad Report.