Kinda superficial discussion on socialism, but that's half expected. It's not the main point of the Manga. The author's MO is to use ethics as a topic to present how a japanese HS student would understand and apply that concept in their own lives. The point is to show how there's competing ideologies and how common sense would see it as 'me the isolationist', 'they the sheeple'.
And how ethics can elevate that common sense to 'collectivism due to the historical development of an agricultural society'.
Even tough it takes some shortcut, I think it's great if it makes people see there's more to things than they initially thought. That things are historically determined.
@Sep10trion
The Black book of communism is not a good source. Besides the criticism already stated in the wiki, a good counterargument is that no country has ever purposefully created hunger; it is disingenuous how the authors claims that number of deaths, without mentioning that a good portion is due to hunger caused by exceptional climate and trade sanctions from western powers.
In the case of sanctions and trade war, you could even tally those deaths as caused by capitalism. The other argument is that capitalism kills a lot more than sociaism, especially the US with its unending wars.