Environmental art

At what point do we become responsible for what we have created? The question can have many responses, one major one being human as agent or art artist as agent. In the act of trying to convey a political and social cultural issue, "we" become part of the issue. I create a body of work in hopes of having an impact on the viewer. Impact can of course be only described in my case as a strong emotional response and ineffect evoke change. Yet the question is, is it moral to create a work, that can not be returned to earth without an impact?