Says the Elusive Wapiti (blog no longer available):
But what feminists didn't realize at the time they took patriarchy out back and shot it is that patriarchy, among other things, lassoed men into socially constructive behavior and dutiful service of society as a whole. And women in particular. Freed from patriarchy, men were free to throw off the yoke of duty and other-focused behavior and could pursue their own self interests full-tilt. Which quite a few dudes did, and found that a world without patriarchy--the world that women all yelled and screamed and marched and burnt bras for--suited them just fine. And they thought that this world was the one that women wanted.