Nationalism promotes hatred and injustice.
Truth does not change just because people do not like it!
As long as there are Flags and Statues, there will be hatred and division. As long as there exist two people of differing ideologies, base bias will always exist. Until humanity, as a whole, become one mind and heart for the sake of itself, there will be hatred and prejudice. To say that love and peace can exist alongside nationalism and politics is entirely counterintuitive.