Even if fusion would be available tomorrow as a viable energy source, which would be great and surely help, it is still would not be a solution for all issues. There is no magic button someone could push or one key technology we have to develop here and suddenly all issues from the destruction of habitats to exploiting of natural resources would suddenly disappear. I am afraid any changes have to be much deeper because the issues we're facing are systemic. So the solution has to be a systemic one as well. The question is only, how much time do we still have for the transition and how can the transition be achieved without actually destroying exactly the thing we try to preserve. A good and decent live.