Copyright only covers the artist's life plus 50 years.  The Berne Convention
adopted in 1988 by the U.S. usually includes a droit moral (moral right) but
the U.S. did not adopt the moral right section (in foreign countries such as
France the moral right can be protected by heirs, etc in perpetuity, others
artist's life + 50 or 70 yrs. I belive).  The U.S. did adopt the Visual Artist
Rights Act (VARA) in 1990 (enacted in 1991) which does include a moral right
for visual artists only and only for the life of the artist.  VARA includes 3
forms of protection for visual artists: (1) right to attribution, (2) right to
integrity, and (3) the right to protect from destruction (such as in a visual
art work is part of a building).

Ginger M. Young