To understand the suffragists, and why their battle took so long, you also have to understand the anti-suffragists.
The sinking of the Titanic in 1912 inspired a flood of articles on seemingly every aspect of the disaster. One of the oddest appeared in The Woman's Protest, a journal dedicated to opposing women's suffrage.
In ''The Lesson that Came from the Sea,'' Josephine Jewell Dodge, a leading anti-suffragist, noted that when the ship started going down, the cry that went up was not ''Voters first!'' but ''Women first!''
''In acquiescing to that cry the women admitted that they were not fitted for men's tasks,'' Dodge wrote. ''They did not think of the boasted 'equality' in all things.''
This was not to say, she emphasized, that women were ''inferior.'' But the disaster, she wrote, ''tends in its terribly grim way to point out the everlasting 'difference' of the sexes.''
Women at the polls (and on the ballot) are such an ordinary sight today that it can be hard to remember how long and hard women fought for the vote and the powerful forces arrayed against them, including business interests, religious organizations and the political parties, which feared an influx of unpredictable new voters.
But one opposition group has long inspired puzzled reactions, if not outright disbelief: women themselves.
As the suffrage movement picked up steam in the late 19th century, it was increasingly countered by an organized, women-led anti-suffrage movement, which mirrored its arguments, tactics and public relations strategies, including cartoons, buttons, pennants and other swag.
It's tempting to dismiss the Antis, as they were sometimes called, as a bizarre footnote, or a joke. But historians argue that you can't really understand the suffrage movement -- and today's unfinished debates about what true equality for women means -- without them.
''You might ask, 'How could a woman be opposed to her own rights?''' said Susan Goodier, a historian at the State University of New York, Oneonta, and the author of ''No Votes for Women,'' a study of the Antis. ''But you have to understand what the suffrage movement was up against, which wasn't just men.''
In the 19th century, when women first articulated the demand for the vote, the idea that politics and government were the sole province of men, who would represent the interests of their families, was the default position of just about everyone.
The idea of women's suffrage was seen as radical unto absurd, even to some early feminists. When a group sat down before the Seneca Falls, N.Y., women's rights convention of 1848 to draft a document calling for equality, Lucretia Mott, a Quaker feminist, warned against including a call for the vote, lest it ''make us look ridiculous.''
And almost as soon as suffragists began formalizing their demand for the vote, other women moved to counter it. In 1871, in response to a proposed 16th Amendment that would enfranchise women (after the 15th enfranchised only Black men), 19 wives of Republican senators, Civil War generals and cabinet members published a petition against it.
In the following decades, other ''remonstrants,'' as anti-suffragists were known, also pressed the case against the vote, even as they strove not to draw too much attention to themselves, in keeping with the common belief that women should stay in the domestic sphere.
''Unlike suffragists, who wanted everyone to know names and recognize their images, the Antis didn't want to be known,'' said Allison K. Lange, the author of ''Picturing Political Power: Images in the Women's Suffrage Movement.''
That changed as anti-suffragists started to get organized, and politicized. The first organized group was founded in Massachusetts in 1895, in response to a campaign to extend municipal voting rights to women in Boston. Later, the movement was based in New York, with national offices, at one point, in the Waldorf Hotel.
While a range of women opposed women's suffrage (including the anarchist Emma Goldman, who saw the electoral system as a tool of the powerful), the organized anti-suffrage movement consisted mainly of elite white women, often married to prominent men. (Goodier has written that there is ''virtually no evidence'' of any Black women in the organized anti-suffrage movement.)
Still, they were not all mere ''butterflies of fashion,'' as one suffragist publication put it. Many were active reformers, sometimes pushing for the same causes -- child welfare, workplace safety, access to education -- that suffragists championed.
The anti-suffragists (who received admiring coverage in The New York Times) included women like Helena de Kay Gilder, a trained artist and future founder of the Art Students League of New York. In a widely reprinted 1894 essay, written in response to a proposal to remove the word ''male'' from the New York state constitution, she laid out her case.
Women ''are men's equal, and almost as well educated, as good and as intelligent in ordinary matters,'' she wrote. But the ballot was a burden that would corrupt and ''unsex'' them, and take away their ''liberty.''
Dodge, the author of the Titanic polemic (and the daughter of a pro-suffrage governor of Connecticut and a suffragist mother), worked to establish nurseries for poor African-American children in Harlem.
And then there was Annie Nathan Meyer, a founder of Barnard College, whose debates with her sister Maud, a leading suffragist, drew attention in the press, which called them ''the fighting Nathan sisters.''
The Antis, scholars note, were not simply saying that women should just stay home. Instead, many believed that participating in the grubby world of party politics would undermine women's distinct strength: their nonpartisan, politically disinterested commitment to the public good.
''These women have a whole idea of what women should be doing in public life,'' said Susan Ware, the editor of a new Library of America anthology about the suffrage movement. ''They just don't think women need or want the vote.''
Toward the middle of the 1910s, as the battle over the proposed 19th Amendment heated up, men came to dominate the anti-suffrage movement. In 1913, a group of prominent men formed the Society for the Prevention of Cruelty to Women, which became more commonly known by the even more Monty Python-esque name of the Man Suffrage Association Opposed to Woman Suffrage.
After World War I broke out, anti-suffrage women shifted their focus to war preparedness and support for the Red Cross. As men took control, the Antis increasingly made states' rights arguments. Anti-socialist rhetoric also rose, with suffragists increasingly denounced as enemies of the state.
After the 19th Amendment became law in 1920, anti-suffrage women went in varying directions. Some, like Meyer, became active in the nonpartisan League of Women Voters. Others became active in the Republican Party, helping push it to the right. By the 1920s, the scholar Rebecca Rix has written, the Antis shed their elitism in an effort ''to make anti-Progressivism appealing to a conservative working-class and middle-class electorate,'' including the women whose voting rights they had opposed.
And some Antis got caught up in the first Red Scare. In 1918, The Woman's Protest had been renamed The Woman Patriot and dedicated itself to''the Defense of Womanhood, Motherhood, the Family and the State AGAINST Suffragism, Feminism and Socialism.''
Some scholars draw a line from the Antis to post-World War II conservative women activists like Phyllis Schlafly, who mobilized a political army against both Communism and feminism.
Ware, no fan of the anti-suffragists, said they became ''more interesting'' when seen as forerunners of later conservative women. But she said there are also differences between the Antis, who saw the vote as a ''burden,'' and Schlafly, who warned of the loss of feminine ''privileges.''
In a recent article in The Los Angeles Times, Gloria Steinem and Eleanor Smeal criticized ''Mrs. America,'' the FX series about the battle over the Equal Rights Amendment, for presenting a ''catfight theory of American history.'' The series, they argue, also exaggerates the importance of Schlafly and her group STOP ERA, which they maintain was less crucial in defeating the amendment than the insurance industry and other corporate interests.
Some historians have made similar arguments about the Antis, whose opposition, they say, was far less important than business interests, the political parties and men in general -- who, after all, were the ones who decided whether women would be allowed to vote.
But still, they argue against being too quick to write the Antis off simply as history's losers.
''It's not what we would think today,'' Goodier said of their arguments. ''But they have their points. Can we be so liberal-minded that we can see equality with nuances of difference?''
Jennifer Schuessler is a culture reporter covering intellectual life and the world of ideas.
PHOTOS: An anti-suffrage card from 1915. (PHOTOGRAPH BY KEN FLOREY SUFFRAGE COLLECTION/GADO/GETTY IMAGES) (TW28); Like the suffrage movement, the organized anti-suffrage movement used posters and other paraphernalia to promote the cause. (PHOTOGRAPH BY BETTMANN/GETTY IMAGES) (TW29)