I’d say that most liberals are not very religious and don’t accept the total depravity of mankind. They think society can continually be improved by science, technology and intellect. Thousands of years of history seem to be irrelevant to them. Too many people demanding individual freedom works against their agenda.
They always say, just like with the latest economic bubble...
“This time is different! Now we have birth control, air conditioning, electric power. People have changed.
This time is different!”