why were the 7 boys hated and blamed?

All the 7 characters had nothing to do with the war. They were around at the time, but they didn't fight in the war nor did they commit any war crimes. So why are they hated by society and blamed for the war, being considered "the scum of Japan". It doesn't make sense. I saw the while show, but it still didn't make sense. Can anyone explain why or give suggestions what the blame and hate is supposed to mean?