Is not nationalism - that devotion to a flag, an anthem, a boundary so fierce it engenders mass murder - one of the great evils of our time, along with racism, along with religious hatred? These ways of thinking - cultivated, nurtured, indoctrinated from childhood on - have been useful to those in power, and deadly for those out of power.
Howard Zinn (2013). “A Power Governments Cannot Suppress”, p.143, City Lights Books