Lets bring it down to brass tacks.
Womanist movements(I'm using the word to lump together all abolitionists, suffragettes and feminists) have always exerted a far larger influence then their actual representation in the hierarchy of power. Suffragettes did not have a vote yet they successfully lobbied politicians to give them one. If those politicians had been in a patriarchal culture they would have been actively against women gaining any power. If they had been in an equitable culture they would have pointed at women's power as wives and mothers and said "checks and balances, m'lady, sorry."
Likewise women today comprise the minority of power positions in, for example, the corperate hierarchy, yet they exert far more influence then their presence should justify.
How do women manage this? What is this mysterious power that women have to force politicians (prior to attaining the vote), corperate heads, college deans, news editors... to do what they want?
Anyone want to take a stab at answering that?
You are hinting at a number of influences. I personally can identify two that exist at this moment.
1) You have the wife/girlfriend factor. During younger years, a man's sexual desires will cause him to do quite a lot for her, since he wants sex at some level. Also, you can consider the fact that the emotional bond causes the woman to become the man's closest advisor, and her advice might be very bad. Add that in with sexual manipulation (over at the Mancoat forum we call it "shaming tactics"), and a man who doesn't know better will be pulled under a given woman's influence. I'm sure you can dig up plenty of historical and modern examples...
2) You have women's organizations who seem to be able to do this at a second-image level. For those who don't know, second-image theories are theories that analyze groups of people as organisms. In this case, we see the first image, wives and girlfriends, exerting influence as one great organism, "women," against other organisms that were present, such as "business," "government," "the churches," and "men." To see how this happens, look at the way immigration is being handled right now. The "against immigration" group exerts influence by putting national media attention on the matter (remember the Minutemen movement and the controversy it caused?) The result is that "government" will be influenced by the fact that the "against immigration" group has been mobilized, and will provide a significant number of votes, not to mention the fact that images of angry armed men roving around the border are unacceptable. Now look at the "for immigration" organism. It is also getting national media attention, and has organized it's own voting machine. The fact that undocumented workers work for less money influences "business" into their favor, and the "business" organism thereby looks to exert influence on "government." Also, the promise of all the votes of naturalized illegal immigrants represents a prize to a significant number of those in "government." Who wins? It depends on the amount of power either group has, and who persists longer.
Now look at the "womanist" movements. Think of what benefits they can offer to organisms like "business" and "government." In particular, look at buyer loyalty and voter loyalty that is promised by advertising agencies and feminist groups, respectively. If the womanists groups are persistent enough, and the potential benefits are great enough (you'll get millions of votes if you do this), then other organisms will, typically, cave in. In theory, this means that any movement can come out of nowhere, and influence any authority it wants and win, if it can become large enough and pester a target authority long enough. This was true with feminism, gay rights, the union movement, democracy, pretty much everything. Referring back to Laborato's theorum, this is because the organism of "government" will act based on extrenal and internal influences, and even if internal influences such as beliefs are against a movement (such as feminism), it will not matter if said movement can have enough of an effect on *external* influences.
In other words, even if a patriarchal society did exist, the "woman first" organism overran it after generation upon generation of movements. Whether the first generation of "women-firsters" had planned to create the world we live in now, I don't know, but it does seem that we have seen a slow, methodical attack on men and masculinity for at least 100 years. Before then it was accepted that men and women were not perfect and that both had to "grow up and get along," but if you read your history, as early as the 20s the idea that women had the right to expect whatever they wanted from man came about, implying it didn't exist before. Like I said, I don't have a humanist explanation about why feminism came about, but I do think that, historically speaking, something like feminism comes into existance, gains power, and later wanes in the wake of another movement, or the collapse of a society. What the dynamics are, I don't know, but this seems to happen across cultures and across time.