> Is it though? This can mean anything. Is waving a Palestinian flag the same as waving an Israeli flag? Where do we draw the line between harmful and productive nationalism? Who exactly is blinded by nationalism?

Clearly it depends on your actual object-level position on the Israel/Palestine conflict. Or in general, what specific nationalisms you mean when you talk about being "blinded by nationalism".

And that's the main reason why I think this is a mediocre piece of art. Very few people actually are genuinely anti-nationalist for all possible human groups that have some sense of themselves as a nation. All anti-nationalist rhetoric is implicitly aimed at a specific nationalism that someone has a problem with - and also everyone knows this. So everyone wants to use the blank slate of bansky's featureless flag as a canvas upon which to paint a nationalism they don't like in order to discredit it. And I personally think that's boring. Maybe engendering that reaction was itself part of Bansky's artistic vision, but I still don't think that makes for good art.