Cross-cultural study shows us that monogamy is required for a stable, future-oriented, low-violence society. No non-monogamous society has managed to achieve a fraction of what predominantly monogamous ones have, and civilizations become more monogamous (by necessity) as they develop.

The danger of accepting and encouraging casual sexuality is that it inexorably leads to strong-man polygamy and the subjugation of women, which most people would consider a regression.