The year is 20XX, state of the world affairs is changing at a dizzying pace. This is particularly clear in the growing military strength of countries neighboring Japan. In response to a near-skirmish with China over the much-disputed Senkaku Islands, Japan launched the state-of-the-art aircraft carrier Note: It can be assumed that the story take places in 2014, the year of the series initial release. As mentioned in the manga; "60 years since the establishment of JSDF" (1954).