It is a naive society that looks on at its past and proclaims its actions
as a kind of pure evil that cannot be understood. You understood it as
well then as you understand it here now. Society has no mechanism for
learning that nearly rivals its constituent's analogue of learning—
merely the perception of a progression due to the passing of time,
and it is foolhardy for a society to think better of itself because
it has not been tested, or worse, does not see its own failure. This
naivety seeps into the people, and those who view themselves as
having a place as part of society, in any sense that they actively
contribute to, in the same motion cement their role in being its dutiful hand.
The only betterment that has ever meaningfully occurred in a society
is the change in its conception of virtue. The will to be 'good'
exists in limited supply, and can only do so much even when directed
the 'right' way, when placed in opposition to more common opposing
wills. Many of these wills, among the ranks of for love, for survival,
for happiness, for revenge, among other things, are not inherently bad.
Marking each of them as such might mean losing something great, even
if it is in some sense true.
Regardless, this is the plight of mankind coordinated: to suffer the
tar pit of their brethren. And if they fancy themselves a
well-adjusted part of it, to perhaps pull the tar a bit further
so that their children may then trudge on with slightly more freedom.