They (= Mankind) have learned the technique of world-wide mutual destruction but not the more desirable technique of world-wide co-operation. The failure to learn this more desirable technique has its source in emotional limitations, in the confining of sympathy to one's own group, and in indulgence in hatred and fear toward other groups.
Source: Bertrand Russell: A Philosophy of Our Time (1953)
More info.:http://russell-j.com/beginner/1026_PfOT-050.HTM