Firstborn Sons Were Exempt
The eldest son in the family holds a significance for many cultures throughout the world. The firstborn son has held a high status for centuries and holds traditions of family hierarchy and inheritance centered around passing on the family name and property to the next in line. In Japan, this important role of the firstborn son was taken very seriously.
It is custom for the oldest son to live with his parents and take over managing the affairs of the family. He has the responsibility to care for his aging parents and provide direction to other family members. When he marries, his wife and children are also included in the household of his parents.
So in 1944, when kamikaze pilots were being selected, firstborn sons were allowed to continue their lives in order to carry on the family name and support their families. This is a definite juxtaposition to the idea that all men were subject to sacrifice themselves in service of the emperor.
Second-born sons were not so lucky. In a personal account of his life as a second-born son and kamikaze volunteer, Paul Saneaki Nakamura talks about his training. He recounts his training took place on the mainland, using gliders instead of planes due to the critical shortages in Japanese aircraft. Luckily, he was never called up for a suicide mission and believed he was returning to his life. However, he would soon discover that nothing was the same.
After the war, Nakamura could not afford to fly back to his home in Okinawa. When he finally returned, he found his community was devastated. He discovered that while he was away, all of the first sons who had stayed behind had been killed during the Battle of Okinawa. It was then that he decided to devote his life to becoming an Anglican priest and spread Christianity across Japan. Later in life, Nakamura became a bishop.