The USA is a nation designed for sane, rational people who want to live happily in this world (emphasis yours).
You have absolutely no concept of Christianity, do you? The vast majority of Americans believe in an afterlife better than this one.
A satisfying sex life with one's husband or wife is necessary for that happiness.
Did you actually manage to find a spouse who shares this shallow view?
When the sole purpose of sex is procreation, love and intimacy, because they tend to culminate in sex for its own sake...
So love and intimacy tend culminate from sex is only for it's own sake?
...become problematic, as does the happiness which results from that love and intimacy.
This is a view of sex as nothing more than a drug.
...and as it detracts from individual happiness, is morally wrong.
A morality of self gratification? This is called hedonism.
Contraception changes that.
So contraception makes sex morally right? Can I then assume that you believe that sex for procreation is morally wrong?
A religious argument which posits that taking the pill is the first step on a slippery slope to abortion as contraception requires faith to convince
The abortifacient aspects to hormone based and IUD type contraception has nothing too do with religion, it is a scientific fact.
This post represents a remarkably sad world view. I hope for your sake that you were just trolling.