The warning signs have been there for decades. Back in 1983, American author Barbara Ehrenreich wrote a powerful book — The Hearts of Men: American Dreams and the Flight from Commitment — arguing that a male revolt was underway. Since the 1950s, she suggested, men had begun rebelling against the breadwinner ethic, inspired by Playboy culture, the counterculture and a desire for personal freedom. They were rejecting the cultural ideology that had shamed them into tying the knot and becoming a good provider, lest they be seen as immature, irresponsible and less than a real man.Ehrenreich understood that marriage was...