Ehrenreich emphasizes that the economy changed dramatically during the post war boom, and the changes in the economy eventually demanded changes in the culture. Women have always worked, but they use to work at home on a farm. Even as late as the 30s and 40s America was still heavily agricutural. But during the 50s and 60s farm life died out in America, not totally of course, but to a large extent, replaced by big industry and then computers. On a farm a woman could do valuable work, in the new world of the 50s there was nothing for a woman to do but sit around and look pretty. You had millions of women of intelligence and strength and a desire for meaningful labor, and they no longer had an outlet, because they no longer lived on a farm. On a farm the could help their man and their family everyday, in a meaninful way. In the 50s, they were mere parasites, living at home in ease while the men worked. And eventualy, of course, the men got tired of that arrangement. To put it another way, on a farm, a man needs a wife. In the modern world, a man doesn't need a woman as much, or at least not in the same way. At some point, the culture had to adjust to the changes in the economy, and that adjustment was feminism. Women had to work so they could still contribute something meaninful to a marriage.