An act of rogue design?

The New York Times just published an article the mysterious appearance of Arabic graffiti in the HBO series Homeland.  Appearing in the background of a scene depicting a Syrian refugee camp was graffiti reading "There is no Homeland" and "Homeland is racist."

The producers hired designer Heba Y. Amin (MFA Design, Minnesota) to help transform the set, a Berlin street, into an unnamed Middle Eastern venue. Interesting that the Times called these communications"street art."  When, I wonder, is something "art" and when does it get counted as an act of rogue or subversive "design activism?"