I actually can’t believe Buronson (aka Yoshiyuki Okamura who wrote Sanctuary) wrote this manga, it’s both hilarious and pathetic. The core concept is sound, but the actual execution is not only awful but insulting, hypocritical and misses the mark so badly.
The idea of commenting on Japan, its identity, its possible future is all well and good, but there's no commentary on Japan's own misdoings (its treatment of indigenous people or neighbouring countries, etc), not even sly winking, it’s all played very straight-faced which makes it look like fascistic propaganda.
The story itself is very simple, which is not a problem in itself as the most classic parables of humanity are simple in nature, but this manga’s simplicity is indicative of its bone-headedness. The art is reminiscent of Miura Kentarou’s Berserk but lacking vitality, skilled composition or anything resembling worthwhile imagery in general.
The last speech at the end of Japan is so bizarre it’s like the author not only forgot what he was writing about, but the name of the manga itself.
Very disappointing output from an author and artist who are capable of so much more and have indeed gone onto better things. Avoid this.