Not to go all JR on everybody, but...
The tipping point for condoms in general in American culture was during the great depression when the US Army began to issue them to soldiers, a result of War Department studies after WWI where they estimated they had well over a quarter million cases of venereal disease casualties among the troops in Europe. Millions and millions of soldiers and another World War later, most state laws against selling any form of contraceptives had been repealed, and usage was much more acceptable to the whole culture with all those G.I.'s back in civilian life, aside from religious issues.