Oh come on, none of this 'your culture is somehow inferior.' What are you talking about? More of this B. S. that I am some shallow product of my culture. Of course to some extent we are socially molded but there seems to be a trend...
Inferior? That designation is not even part of the scale. There's no "superior", either as far as cultures are concerned - just differences. Not
ethics might be a different matter altogether, as certain forms of social progress are inherently tied to improved living conditions, but culture in general is not open to such evaluations.
A tuxedo is not inherently "superior" to an Indian Sherwani, a Japanese Samue or even a traditional New Guinean penis sheath.
Americans are sexual.
Koreans are sexual.
Korean-Americans are sexual.
Being sexual is not the problem. Every people on the globe is sexual.
Being sexually *neurotic* is the problem. I don't know enough about Koreans to comment on that, but Americans approach sexuality (or even nudity) like immature teenagers.
There will always be sexual tension when faced with the gender you are attracted to naked, unless it is someone who is too old or too young to be sexually attractive.
The same goes for being in the presence of the same persons wearing clothes, especially if the clothes aren't exactly designed to hide their body forms altogether. Non?
I am a male and I associate nudity with sex. Probably because sex involves genitals that normally are clothed. Perhaps if I walked around naked all day long with other nude people I would lose such a context.
I take it you've never been to a nude beach, then? Yes, you'd quickly lose such a context. More quickly than you might think possible.
We are animals, are we not?
We evolved, did we not?
Do we not, then, have some instincts that cannot be muted -- instincts to breed?
If we were like most animals we'd even approve of rape as an acceptable means of reproduction.

Just a thought.
Comparing ourselves to other mammals, even our closest "relatives", brings up an interesting issue.
Out of all the great apes, we are the only ones who know neither mating seasons nor a means of telling whether a woman is at the fertile point of her cycle or not. Contrasting our most instinctual (read: not culture-specific) sexual behaviour with that of our closest "relatives", the genus "pan", leads me to the following hypothesis:
social mammals living in extended groups need some means to regulate sexuality, lest the pent-up energies rip the group apart. The patriarchal chimpanzees do so by establishing an aggressive, male pecking order; the matriarchal bonobos do so by mating freely and for fun, appeasing aggressive males by re-directing their energies "elsewhere". And Man apparently does so by restricting sex to the private sphere as much as possible.
By the way, evolution describes an "is", not an "ought". And yes, for most of our history, Man had little moral inhibitions with regards to rape, especially when it came to women of foreign tribes or nations. It is blandly referenced without the least hint of guilt or conflict in Roman, Greek and Hebrew writings, for example.
And it's not as if this mysteriously stopped with the onset of the (post-)industrial age, either: the Japanese Imperial Army kept whole camps filled with "comfort women" of Korean or Chinese stock, forcing them to work as prostitutes; the Russian Red Army raped thousands of dispossessed German refugees (among them my grandmother) in 1945; the Serbs systematically raped Croatian and Bosnian women in the 1990s. And so on and so forth. Even if we restrict it to instances such as these, where these deeds weren't isolated incidents committed by rogue soldiers acting on their own, we could come up with quite an impressive list for the 20th century alone, I am sure.