Russia decided against attending the Hiroshima ceremony commemorating the atomic bombings, although it had participated in similar events in Nagasaki. The absence caught attention due to the significance of these ceremonies in Japan which symbolize the country's commitment to peace and nuclear non-proliferation. As of now, the reason behind the Russian delegation's absence remains unclear.

The Hiroshima and Nagasaki ceremonies are extremely significant in Japan. They represent the national trauma from World War II and the nation's commitment to a peaceful future, free from nuclear weapons. The absence of international participants, particularly from powerful nations like Russia, can send a negative signal about international commitment to these principles.

In the US or EU, the absence of a foreign delegation at a significant commemorative event would be considered a diplomatically disrespectful act. Such actions can strain international relations and are generally cautioned against unless there is a significant controversy or political issue at play.