We Had Flags

A law doesn't work if everyone breaks it.
For forty years, New City has been a bastion of order in a fallen world. One crucial law has maintained the peace--it is illegal to place responsibility for the collapse of civilization on any one group. Anyone found guilty of Blaming is branded and stripped of citizenship.
But when some unwelcome visitors arrive from across the sea, old wounds break open, and no one is safe from Blame.