In my opinion it all comes down to the most deadly phenomenon of the Twentieth Century - the substitution of ideological models of reality for rational thought.
In many parts of the world this led to millions of people dying horrible and painful deaths. In the English speaking world I suspect that many problems, that we experience today, are due to those in authority appearing to espouse a vaguely lefty, liberal philosophy in their public utterances whilst, in practice, trying to run things according to the mad principles of free-market capitalism - two mutually incompatible ideologies.