Men in Afghanistan also have this practice of using boys for sex. I have wondered how human societies can become so abhorrent, my belief is that probably at some time in the past there was some really sick leader who pushed his perverted ways on the culture, probably a pedophile who preferred boys and had access to many young boys. The young boys probably grew up to prefer male sex partners over females and the pattern became set in the culture. What you said about enemy nations taking over the perverted nations is probably true as perversion over time will emasculate the culture, a more masculine culture will probably move in. It might take centuries for a culture to collapse but it could be a long time pattern.
It doesn't seem as though the US is taking very long to make buggery a legitimate sexual practice seen by a great many Americans to be as normal as male/female sexual relations. Needless to say, God isn't going to tolerate this rebellion against His established order of nature indefinitely. His wheels grind slow, but they grind very fine.