Interesting topic...
Uncle Frank... great reply "I think hormones are behind the steering wheel and lust is in the passenger seat."
This is a great topic, comparing Japanese values with American values of pre-marriage sex, marriage, and relationships. Everything is changing on the America side, and not for the better, I feel.
American society is breaking down on this issue. When sons and daughters don't know who there father is, it creates climates of unrest and depression and dissension. American society of old almost held sacred the father/mother relationship, divorce was rare, marriages were more long term and probably unhappy too, it didn't matter, you tried to stay married for the sake of the children.
Today, the American "normal" average is multiple parents, for multiple marriages, with multiple children, and even a growing multiple "relationships" outside of marriage, while married.
Lack of a father figure, or known father parentage is rampant in certain ethnic cultures, within America. This is a horrifying fact, well known.
But maybe that subject is not this topic, really. Sex before marriage is expected in America, as a normal right-of-passage, and frankly, nobody expects any different when marrying someone. I am not saying that is good or bad, but it is a historical fact for America. Pre-marital sexual contacts and relationships are the overwhelming norm, and expected.
What is a curious development is the trend nowadays towards rejecting the institution of marriage alltogether. Why get married when living together, unmarried is acceptable. The political legal machinery for divorce is so dysfunctional in America, so devastating, so mentally and emotionally catastrophic, with lawyers transferring the hard-earned lifetime wealth from the divorce parties to themselves, couples are rethinking the whole process of marriage. What is the point, just have sex, just live together.
But again the American family unit is so dis-integrated, so broken apart from the families of old, I tell my sons... don't marry a traditional American woman. Marry a foreigner, who has a strong family value system, and certainly Japanese/Asian women are highly regarded by Americans in these area of family, morals, and character.