Caroline Norma lectures in the School of Global, Urban and Social Studies at RMIT University.

At least since the sexual revolution of the 1960s, Lefties have been rankled by the presence of feminists among their ranks.

But purging these uppity women presents a challenge. Overtly denigrating feminists is risky: it can be perceived as misogynistic, and cedes too much political ground on issues lefties like to call their own - such as abortion rights.

Unfortunately, prolific and global male crimes of incest, rape, prostitution, domestic violence, female genital mutilation, child marriage and acid attacks make the feminist cause a bit too justified, and a bit too popular.

So the Left is stuck with having to marginalise through covert means the political movement organised to resist male supremacy and its violent war against women and children.

An effective covert tactic has been to play wedge politics.

Marxists, peaceniks, greenies, queers, animal libbers and some anti-racism groups over three decades have been remarkably united in their commitment to purging feminists from the Left. All agree the womanly concerns of feminists are small-worldish, and tainted with embarrassments like female ageing and poverty. They are unsexy, child-focused, lesbian-loving and distract from the Left's pursuit of "serious" issues like atheism, nuclear proliferation and ecological destruction.

Feminism's mission to dismantle male sexual entitlement is offensive, and inconceivable as a political project even among those who challenge entitlements of meat-eating or capital accumulation. Feminist priorities can also be inconvenient for adored male leaders: the Left rues the fates of Roman Polanski and Dominique Strauss-Kahn, ignores Woody Allen's daughter, and defends Norman Mailer and Allen Ginsberg.

Leftist tactics against feminists are politically sophisticated, and increasingly so. They have to be: social science evidence of male violence against women and children has piled up over the years, its victims are increasingly organised, and international institutions have been remarkably receptive to feminist thinking and arguments. In this sort of climate, discrediting, ostracising, ridiculing and marginalising feminists is no easy task.

The Left has nonetheless managed to purge feminists from its ranks more successfully today than at any time since the Second World War. Pitting women against each other, first, through bastardising a core feminist demand, and then, by turning it into a wedge issue around which dissenting women are vilified, has proven to be a winning formula.

The Left's first victory came in the 1980s. Throughout this decade, feminist opposition to pornography was beginning to gain traction as a wedge issue. As a result, an entire generation of feminists was driven from the Left for refusing to adhere to the newly minted idea of the sexual revolution that pornography was an expression of women's political freedom.

In 1987 Andrea Dworkin wrote that the Left "cannot have its whores and its politics too," and was thereafter branded - along with Catharine MacKinnon - its arch-enemy. Dworkin and her ilk were cast out, and their work in support of the world's most abused women never attracted broad progressive support. The global sex industry was the direct beneficiary of this win against feminists of the 1980s.

A subsequent generation of feminists in the 1990s was defeated, again by a Leftist wedge tactic, but this time the long history of feminist abolitionist campaigning against prostitution was the core demand turned upside down. Instead of sexual slavery, the Left reconceptualised prostitution as a form of work for women, and a consumer service activity for "clients." Feminists who failed to parrot this newly conceived idea of "sex work" were chased out, and women got rewards for doing the chasing. Academic superstars Martha Nussbaum and Ueno Chizuko were just two of many who got on board.

Prostitution was a particularly cynical choice for the Left as a wedge issue in the 1990s; before this time, opposition to prostitution had been a central pillar of its thinking and campaigning. The 1848 Manifesto of the Communist Party had called for the "abolition of the community of women springing from ... prostitution both public and private."

By the twenty-first century, however, both prostitution and pornography have lost some of their strength as wedge issues: the global sex industry's horrors and hangovers were too stark.

The Left today is nonetheless achieving a purge of feminists from its ranks unrivalled by their previous successes of the 1980s and 1990s. Playing wedge politics is still the tactic of choice, but the issue requiring women's pledge of allegiance is brand new.

Transgenderism bastardises the core feminist insight that "woman" is a politically defined social category generated by male violence and the exclusion, expropriation and colonisation of female human beings. Rendered as a Leftist wedge issue, this insight becomes the distorted proposition that "woman" is a flexible human "identity" with which any individual might associate themselves - even fully-grown rational male human beings.

Rather than being a designator of subordinated social class membership, "woman" is a feeling that can swell in any man's breast. Acting on this feeling, he might adopt sex-stereotyped clothing and behaviours, and others must hold these caricatured displays in high regard. Female pronouns must be used, and laws and policies must be changed to newly recognise women, not as an historically vulnerable social group, but as the product of an individual man's inner thoughts and feelings.

The Leftist purge of women who refuse publicly to declare allegiance to such ideas of transgenderism is proceeding apace. It takes the form of the "no-platforming" of feminists at speaking events, the petitioning of conference venues to drop bookings from feminist groups, the public harassment and ridicule of dissenters, and lobbying for women to be removed from jobs and positions of public profile.

Janice Raymond, who authored The Transsexual Empire: The Making of the She-Male back in 1979, is still being targeted by Leftists in these ways. Sheila Jeffreys endures the same fate since the publication in 2014 of Gender Hurts: A Feminist Analysis of the Politics of Transgenderism . Julie Bindel wrote a series of articles criticising the biological essentialism and homophobia of transgenderism, and for her efforts receives death and rape threats. So too does Cathy Brennan for maintaining an online database of transgender-related legislation, criminal cases and police reports.

Most recently, Germaine Greer has hit back in the media about the public sanction, harassment and exclusion she faces for refusing to recognise transgender men as women.

Her comments are notable for their attempt to get behind the wedge issue that transgenderism represents and address the real issue of misogyny on the Left that motivates its ideological spread.

In her discussion, Greer repeatedly flags the especial woman-hating that is reserved for female elders in Western societies, and entreats viewers to "try being an old woman!" and "try running with sagging breasts down the middle of the street" in response to the interviewer's questions about transgender displeasure at the prospect of not being recognised as women.

This comparison of male hurt feelings with the violence, poverty, ridicule, disgust and social erasure that older women inevitably endure goes to the heart of the Left's misogyny: never in history have we seen a broad-based progressive social movement dedicated to championing the rights of the group of human beings who are devalued in male sexual terms as no longer having perky breasts or youthful faces. Even though these women make up the most impoverished and despised of all social groups, Greer reminds us that we instead worry about hurting the feelings of men who embark on extreme feminine beauty practices, and champion them as "a better woman than someone who is just born a woman." In other words, anyone is preferable to an old woman, even a man parading as one.

Transgenderism is not a political movement motivated by progressive concerns - it's just the latest weapon in the Left's covert battle against feminism. Women like Greer, Raymond, Jeffreys, Bindel and Brennan who authentically concern themselves with the condition of women at the bottom of the pile are the feminists being purged in the twenty-first century version of the Leftist wedge.

But Greer was politically savvy in insisting her audience acknowledge misogynistic ageism in response to questions about transgenderism. It's a point feminists should continue to insist upon. The Left's woman-hating has a hard time remaining hidden when confronted with the real lives of aged women, even when it's throwing up dust about "cis-sexism" and "fluid identities."

If political wedges are the currency in which the Left deals, let's respond with our own around misogynistic ageism. It will be interesting to see what floats to the surface.

Caroline Norma lectures in the School of Global, Urban and Social Studies at RMIT University.