At no previous period has mankind been faced by a half-century which so paradoxically united violence and progress. Its greater and lesser wars and long series of major assassinations have been strangely combined with the liberation of more societies and individuals than ever before in history, and by the transformation of millions of second-class citizens -- women, workers and the members of subject races -- to a stage at which first-rate achievement is no longer inhibited even if opportunities are not yet complete.