You can boil it down to religious extremism: Puritans (the New World's original religious extremists) propagated their values well. Puritan values (which are ultimately Judeo-Christian) stuck longer in North America.

The Judeo-Christian tradition of heavy authoritarian social traditions (top-down, male oriented, "might makes right" mindset) mutated into what is basically a modern jingoist mentality.

Eventually, you arrive with what we see today: a culture which values strength and fierceness, and reflects this in its movies and tv, while simultaneously holding onto an antiquated fear of/confusion about human sexuality.