Lot chose to go live in the nicest place in Palestine....the area of the plain of Sodom and Gomorra....
And typically where are the nicest, most fashionable parts of cities?
I think in the peace and prosperity after WWII...and the spoiled rotten kids of the '60s, with the sexual immorality being accepted as "normal" the worse immorality of sodomy was bound to happen... The sad thing is though, unless a huge religious revival occurs it will take a SERIOUS calamity to rid America of these practices...and practicioners. That also happened thousands of years ago--and the area of Sodom ain't too pretty now...
Also, human nature is rebellious. Humans naturally find excitment in breaking rules and social morals. This is why as morality declines society totally breaks down as it takes increasingly more hideous acts for people to feel rebellious.
It is known to be the fall of many civilizations before ours.