It’s time to call misogynist extremism by its name.

On Friday night, a young man went on a massacre in Santa Barbara that left six other people dead and seven injured. In the hours before the massacre, the suspect, 22-year-old Elliot Rodger, had uploaded a video to YouTube titled “Retribution”. In this, and in a 140-page manifesto published online, Rodger claimed that he was going to prove himself the ultimate “alpha male” and take revenge on all the “sluts” who had sexually rejected him:

"Tomorrow is the day of retribution, the day in which I will have my revenge . . . you girls aren't attracted to me, but I will punish you all for it. I’ll take great pleasure in slaughtering all of you. You will finally see that I am in truth the superior one, the true alpha male.”

This is not the first time that women and unlucky male bystanders have been massacred by men claiming sexual frustration as justification for their violence. In 1989, 25-year-old Marc Lépine shot 28 people at the École Polytechnique in Quebec, Canada, claiming he was "fighting feminism". Fourteen women died. In 2009, a 48-year-old man called George Sodini walked into a gym in the Pittsburgh area and shot 13 women, three of whom died. His digital manifesto was a lengthier version of Rodger’s, vowing vengeance against the female sex for refusing to provide him with pleasure and comfort. Online misogynists approved.

“When men kill women, the underlying reason is almost always an unfulfilled psychosexual need . . . to men celibacy is walking death, and anything is justified in avoiding that miserable fate,” wrote “Roissy in DC” of the Pittsburgh killing, as reported by Jezebel in 2009. “At least it is implied that feminism is to blame and he is taking a last stand,” said another. “I had been waiting for this (almost thinking I had to do it myself) and I am impressed. Kudos."

The ideology behind these attacks - and there is ideology - is simple. Women owe men. Women, as a class, as a sex, owe men sex, love, attention, “adoration”, in Rodger’s words. We owe them respect and obedience, and our refusal to give it to them is to blame for their anger, their violence - stupid sluts get what they deserve. Most of all, there is an overpowering sense of rage and entitlement: the conviction that men have been denied a birthright of easy power.

Capitalism commodifies that rage, monetises it, disseminates it through handbooks and forums and crass mainstream pornography. It does not occur to these men that women might have experienced these very human things, too, because it does not occur to them that women are human, not really. Women are prizes to be caught and used or hags to be harassed or, occassionally, both.

Violent extremism always attracts the lost, the broken, young men full of rage at the hand they’ve been dealt. Violent extremism entices those who long to lash out at a system they believe has cheated them, but lack they courage to think for themselves, beyond the easy answers they are offered by pedlars of hate. Misogynist extremism is no different. For some time now misogynist extremism has been excused, as all acts of terrorism committed by white men are excused, as an aberration, as the work of random loons, not real men at all. The pattern is repeatedly denied: these are the words and actions of the disturbed.

"All I ever wanted was to love women, and in turn to be loved by them back. Their behaviour toward me has only earned my hatred and rightfully so! I am the true victim in all this. I am the good guy. . . I didn't start this war."

This is how extremism works. It takes the valid and substantial anger of the dispossessed and tortures it into something twisted. It promises the lost and despairing that they will have the respect and sense of purpose they have always longed for, if they only hate hard enough. And often it starts as a game, as shadow-play.

I make no apologies for the fact that this piece is full of rage. When news of the murders broke, when the digital world began to absorb and discuss its meaning, I had been about to email my editor to request a few days off, because the impact of some particularly horrendous rape threats had left me shaken, and I needed time to collect my thoughts. Instead of taking that time, I am writing this blog, and I am doing so in rage and in grief - not just for the victims of the Isla Vista massacre, but for what is being lost everywhere as the language and ideology of the new misogyny continues to be excused.

Why can we not speak about misogynist extremism - why can we not speak about misogyny at all - even when the language used by Elliot Rodger is everywhere online?

We are told, repeatedly, to ignore it. It’s not real. It’s just "crazy", lonely guys who we should feel sorry for. But as a mental health activist, I have no time for the language of emotional distress being used to excuse an atrocity, and as a compassionate person I am sick of being told to empathise with the perpetrators of violence any time I try to talk about the victims and survivors. That’s what women are supposed to do. We’re supposed to be infinitely compassionate. We’re supposed to feel sorry for these poor, confused, vengeful individuals. Sometimes we’re allowed to talk about our fear, as long as we don’t get angry. Most of all, we mustn’t get angry.

We have allowed ourselves to believe, for a long time, that the misogynist subcultures flourishing on- and offline in the past half-decade, the vengeful sexism seeding in resentment in a time of rage and austerity, is best ignored. We have allowed ourselves to believe that those fetid currents aren’t really real, that they don’t matter, that they have no relation to "real-world" violence. But if the Isla Vista massacre is the first confirmed incident of an incident of gross and bloody violence directly linked to the culture of ‘Men’s Rights’ activism and Pickup Artist (PUA) ideology, an ideology that preys on lost, angry men, then it cannot be ignored or dismissed any more.

We like to think that violent misogyny - not sexism, but misogyny, woman-hatred as ideology and practice, weaponised contempt for one half of the human race - isn’t something that really happens in the so-called West. No matter how many wives and girlfriends are murdered by their husbands, no matter how many rapists are let off because of their "promising careers", violence against women is something that happens elsewhere, somewhere foreign, or historical, or both. So anxious are we to retain this convenient delusion that any person, particularly any female person, who attempts to raise a counter argument can expect to be harassed and shouted down.

As soon as women began to speak about the massacre, a curious thing happened. Men all over the world - not all men, but enough men - began to push back, to demand that we qualify our anger and mitigate our fear. Not all men are violent misogynists.

Well, there have always been good men. Actually, I firmly believe that today there are more tolerant, humane men who recognise and celebrate the equality of the sexes than there have ever been before. Today, what I hear from many men and boys who talk to me about gender justice - decent, humane men and boys of the kind the twenty-teens are also, blessedly, producing in great numbers - is fear and bewilderment. Who are these people? Where do they live? And the unspoken fear: do I know them? Might I have met some of them, drunk with them? If the wind had changed when I was growing, if I had read different books and had different friends, might it have been me? If any man is capable of this, is every man capable of it?

Well, those are the correct questions to ask. What I hear more often, however, is “not all men”. I hear that age-old horror of women’s anger drowning out everything else. Not all men are like this. Don’t look at us. Don’t shout at us. Please, don’t ask us to stand up and be counted.

One thing I’ve found, when talking to people involved in the savage end of the "Men’s Rights" community, the Pickup Artist scene, or both, is that to a chap they are keen that I understand the difference between their grouplet and the next - those guys over there hate women, those guys over there have a broken worldview, we’re the reasonable ones. And before the charges of book-burning and censorship begin: interpretation does change everything. There are certainly men out there who engage with the ideas of "Pickup Artistry" without absorbing the contemptuous misogyny at its core, much less pursuing it to its conclusion. One of my best relationships, in fact, was with a young man who swore by The Game as a handbook for shy boys who wanted to be able to talk to girls at parties, whilst mocking the sexism at its core.

So no, it’s not all men. But then it never was.

But if you think for one second, for one solitary second, that demanding tolerance for men as a group, that dismissing the reality of violence against women because not all men kill, not all men rape, if you think that’s more important than demanding justice for those who have been brutalised and murdered by those not all men, then you are part of the problem. You may not have pulled the trigger. You may not have raised your hand to a woman in your life. But you are part of the problem.

This is not the time, to use the refrain of apologists for bigotry, to play devil’s advocate. The devil has more than enough advocates today. On most days, I can put up with aggressive faux-objectivity being used to shout down women’s experiences and silence gendered trauma, but not today.

"Women should not have the right to choose who to mate and breed with. That decision should be made for them by rational men of intelligence . . . Women have more power in human society than they deserve, all because of sex. There is no creature more evil and depraved than the human female."

I know for sure that just by writing this I will have exposed myself to more harassment, more threats, more verbal assaults. The comments below this piece will be stuffed, as they always are, with rank sexism, along with by a few brave souls trying to counter their arguments or maintain some pretence at tolerant, adult debate. I have clear memories of a time when I really looked forward to engaging with people who commented on my blog, even when we disagreed, when online politics was an exciting, dynamic space of living conversation. I remember it, and it’s in the cache, so it must have happened. But many young women at the start of writing and digital careers today have no such memories.

I didn’t experience violent misogyny as a child - sexism, yes, but my early years were free of direct experience of woman-hatred against me or my loved ones, except as an abstract concept, the fear that gets taught to all girl-children as soon as they can stand unaided: don’t walk down that street, don’t wear that skirt, don’t speak too loud or upset the men. You’ll get hurt. You could get killed. For today’s girl-children, that has been expanded to include: don’t go on the internet. Bad men are there, men who will hurt you.

Many of us choose to ignore those warnings. We choose to act instead like we are real human beings with a right to take up space, like almost all women and girls who have managed to achieve anything throughout history, because that’s what those warnings are for, what the violence behind them is for - to scare us into submission. We make that choice again every day, and somehow it does not get easier - because the older and stronger we get, the bigger and stronger the new feminist movement gets in all its glorious variety, the more vicious and committed the backlash becomes. The backlash is real. There is ideology behind it. It hurts. Sometimes, it kills.

For the countless women and girls who have come to live with harassment as a daily cost of being in public and productive while female - let alone while feminist - the tragedy at Isla Vista has been a chilling wake-up call. I know I will never be able to tell myself in quite the same way that the men who link me to two-hundred-post threads about how I ought to be raped can’t actually hurt my body, no matter how much they savage my peace of mind.

We have been told for a long time that the best way to deal with this sort of harrassment and violence is to laugh it off. Women and girls and queer people have been told that online misogynists pose no real threat, even when they’re sharing intimate guides to how to destroy a woman’s self-esteem and force her into sexual submission. Well, now we have seen what the new ideology of misogyny looks like at its most extreme. We have seen incontrovertible evidence of real people being shot and killed in the name of that ideology, by a young man barely out of childhood himself who had been seduced into a disturbing cult of woman-hatred. Elliot Rodger was a victim - but not for the reasons he believed.

Misogyny is nothing new, but there is a specific and frightening trend taking place, and if we’re not going to accept it, we have to call it by its name. The title of the PUA bible belies the truth: this is not a game. Misogynist extremism does not exist in a mystical digital fairyland where there are no consequences. It is real. It does damage. It kills. And this is no longer a topic where abstraction is anything approaching appropriate.

Laurie Penny's Unspeakable Things: Sex, Lies and Revolution is available for pre-order.