Stemming from my own experience of September 11th, this poster is focusing on the effect of terror on people who have witnessed tragic events, by telling the individual story of a terror witness. The imagery makes a historical allusion between the Twin Towers and the smoke stacks of Holocaust crematoriums.

The New York skyline is made of rubble

The sulfuric green color alludes to the pungent smell of both 9/11 and the Holocaust. The red type is referencing the poster's call to action, a conference commemorating today's victims of terror.