Interesting point. Wars always stir things up, too - like the WW I song went, "How you gonna keep 'em down on the farm / After they've seen Paree?" In some ways, conventional morality was also a casualty of WW II. Men came back from the war with a very different perspective on life than when they left.
And war, because it reduces the number of marriageable males, puts the surviving males in an excellent bargaining position.
Why do you think Paris was so hot in the 20s ? The First World War killed 29% of all French males between the ages of 20 and 40. That means an awful lot of lonely women who know that marriage is an unrealistic expectation. To varying degrees it was the same througout Europe. Lots and lots of lonely women who have to settle for what they can get created the Henry Miller world full of horny women.