The Toronto van attack that killed 10 people and injured 13 others on Monday caused shock and horror worldwide, and its method immediately raised suspicions of terrorism. Since then we have learned that the suspect appears to have published a post minutes before, claiming to be part of an “incel [involuntary celibates] rebellion” and praising a misogynist who shot six people dead in 2014, saying he wanted to punish women for rejecting him.

The atrocity has shed light on the unsavoury, disturbing internet subculture of “incels”, some of whom have celebrated the crime. They believe they have been denied a fundamental right to have sex with women (more specifically, women they consider attractive). As twisted as this perspective is, it contains a kernel that is painfully familiar to women in particular. Some men believe they have a right to female attention and bodies, and are ashamed and then angry if either is not granted. Some of those will attempt to impose their demands by threat or force. As Margaret Atwood wrote, men are afraid that women will laugh at them; women are afraid that men will kill them.

The structures of male power are ultimately buttressed by the threat of violence; it is no coincidence that suffragettes were sexually assaulted as well as shouted down. Violence against women and girls, often instrumental and sometimes explicitly described as punishment for their imaginary sins, is age-old and global. What is new is the interpretation of a perceived personal slight in social and political terms, and the vow to overturn what incels regard as the current status quo.

Yet the discovery of the post, if anything, steered coverage away from discussion of terrorism – which the FBI defines simply as “the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives”. Details of this case are still emerging, and whether it can be defined as terrorist in purely legal terms is arguable. But misogynist violence is not just a personal issue. It is a social one.

The Southern Poverty Law Center, which monitors far-right hate groups in the US, this year added male supremacy, including incel culture, to the ideologies it tracks. One factor appears to be a backlash against the gains that women have made. Though women are still a long way from achieving parity in pay or other areas, some men believe the progress towards it is unfairly bought at male expense. Like the white bigots who felt threatened by Barack Obama’s presidency, they portray equality as not only a warping of the “natural” order but also a form of oppression.

Another factor is that the internet and social media have facilitated and supercharged this form of misogyny, just as they have allowed a fourth wave of feminism to burgeon. People can more easily find like-minded souls, have their identities reaffirmed, develop their thinking and organise – for better or for worse. Communities can easily turn into echo chambers, radicalising minds and hardening hearts.

So tackling the misogyny of the online world is essential. Yet companies so quick to remove intellectual property infringements have proved ineffectual in removing vile material that demeans or attacks women, or in dealing with direct threats and abuse towards them. This normalises and fosters hatred.

But the internet did not invent such attitudes and instincts. We need to challenge a broader strain of toxic masculinity which equates manhood with the capacity for brute conquest and shames men for any perceived weakness, bringing them misery too. Boys and young men need to know that masculinity does not have to be so narrowly defined and that vulnerability is no mark against them (a message that the grime artist Stormzy sent effectively in acknowledging his depression, for example). You do not have to read very far between the lines of incel forums to detect a festering sense of humiliation and fear that has turned into anger and aggression. There are no excuses for violence. But we cannot tackle it unless we stop treating it as an anomaly, and instead recognise it as an extreme manifestation of a wider problem.