Good question. I think feminism/egalitarianism. But more so because of the larger issue it is couched within, that if the fragmentation of the household.
Everything else I listed is, in some sense, downstream of healthy, in tact, integrated, faithful, and productive households. Households have, until the industrial revolution, been the economic and cultural engines of civilization. They are, as many Puritans saw them, little churches. They are the primary place where life, work, and education happened for ages. They are the lifeblood of local communities.
Feminism didn't cause the fragmentation and degradation of the home, and by extension, the rest of society, but it has perpetuated and accelerated it.
As goes the household, so goes the world.