|"No, I'll go to work and you can stay home with little Barack!"|
But for all of human history-- with a few exceptions, of course-- men have been the primary providers for the household and by implication the master of said domain. Situation's changed now, especially in America, and a cold war has erupted between men and women over who should be topdog in matters of marriage, household and finance.
Men are intimidated by their partners earning more than them (or being sole providers) because earning the most gives you the most power and, by implication, command of the household and its decisions. In a man's world competition is everything and days must be counted as wins and losses. To capitulate to a woman who earns more or holds higher office makes a loser, if you will, out of a man if his manhood is tied to his potential to provide for, and preside over, his family (most men "suffer" from this).
Women often say that they have no problem falling under their husbands but the truth is that the impulse to make a show of power when one has it is as compelling to females as males. And women have more to prove in the 21st century than men, constantly reminding us that they can do what they do, what we do, and all of it better. So you can imagine the trepidation a new millennium man has at being "joined" to someone who's part-woman, part-gladiator.
I'm not making a case for women shutting up and sitting down forever (because that'll never happen), but there has to be a way for a man to keep his worth while a woman measures her own. What does it mean for a woman to be topdog, to swing power like a blunt sword and roar with bloody fangs, if it only earns the enmity of the man she claims to need and love?