I read the title, then thought, well Nationalism is seen as awful because it is ALWAYS associated with Nazism, then I saw the photo. Well, that says it all. When you can only think about Nationalism in this context, there is no discussion to be had.

You might consider a different perspective on the entire thing, you know, outside, of the typical “nationalism == nazism:

http://www.econtalk.org/yoram-hazony-on-the-virtue-of-nationalism/