I think one just has to look at the rest of the animal kingdom (and we humans remain animals despite our cerebral activity) to see that competition for food, territory, continuation of the species, are built into the fabric of all biology and even botany.  I'm the most pacifistic pacifist on the planet, but I don't see deep and permanent changes to our nature happening soon.  Jesus has the radical message of peace but we collectively don't seem to be able to embrace that radicalism (yet).  I think Monica's right.  Maybe the next generation of AI/robots will find the answer; we seemed to have rejected all other answers thus far.