What metaphors are used in Citizen 13660 by Mine Okubo?

The Wakasa Incident involves an elderly resident of the Topaz Relocation Project being shot to death by a watchtower guard under poorly understood circumstances. Other residents demanded to know more about the death, but the U.S. administration kept the circumstances mostly secret. This led to outrage and protest in the relocation camp, to the point the administration moved the watchtowers further from the camp and outlawed firearms among the guards. The incident is a symbol and a metaphor for racism and subjugation of Japanese Americans.