Source: The Censorship Horizon: A Survey of Art Museum Directors, Pen.org Background   A mirror for dissent. That has been one of art’s paramount functions since the busts of  Akhenaten were destroyed  and left as visages for an onlooking public in Tutankhamun’s new eighteenth dynasty. From abolitionist engravings  to  anti-war murals  of the 1960s to human rights activists like   Ai Weiwei,  art has long served as protest speech. American artists have used paint, performance, and public...