On Saturday, at Linlithgow’s bijou book festival, Val McDermid could not tell her audience very much about her new novel, Splinter the Silence, for fear of giving away the plot. What she did reveal, however, is that its subject is the rise of internet trolls, those offensive patrollers of the online world who make twitterers of thin skin and anxious disposition nervous to broadcast even the blandest remarks. If J K Rowling can be savaged for expressing delight at the Scottish rugby squad’s performance in the world cup quarter final, what is safe for someone to say without fear of cyber assault?

McDermid believes that women are far more often the butt of trolls than men, despite the fact she has rarely been targeted. Even when she appeared on Question Time, a programme where, with the exception of politicians, most women’s performance is routinely met by twitter abuse, she emerged unscathed. Perhaps, as her teenage son has helpfully suggested, this is because she looks “so scary”. Or because, as her fiction attests, she knows countless undetectable ways to kill people.

Naturally, her novel takes trolling far beyond verbal bullying, but going to murderous extremes is what crime novelists are paid to do. The rest of us don’t need a string of corpses to feel frightened. It’s enough to read the aggressive, ignorant and often savage online insults some high-profile women endure. You can be sure that Nicola Sturgeon, Kezia Dugdale and Ruth Davidson are all occasional or regular targets of attack. Indeed, it is becoming a fact of life for any woman who airs her views. And while Sturgeon has told those who hurl abuse under the banner of Scottish Nationalism that their behaviour is completely unacceptable, the issue goes far deeper than party politics. Rowling’s unionist convictions are only a convenient excuse for malicious misogynists to lambast her.

Obviously, some men suffer serious online abuse too. And there is the even more disturbing issue of children’s cyberbullying, which has such serious implications for their wellbeing that Prince William and the Duchess of Cambridge have arranged talks with service providers in the hope of helping establish better safeguards. That, however, is a whole other and complex subject. Yet what it does show is that trolling, whatever form it takes, can affect anyone who sets foot on social media. We are all at risk.

But some are at more risk than others. Men’s persecutors rarely invoke rape, or worse. If suggesting that Jane Austen’s head should adorn a stamp can be met with death threats; or when trenchant opinions expressed by the likes of Michelle Mone or Mary Beard provoke some bloke with the emotional intelligence of a mealworm to lash out, under cover of a pseudonym, it suggests that beneath the civilized veneer of our well-educated society, primitive fear and hatred seethe. Are these emotions a relic of the past, or has the anonymity the internet offers allowed a modern breed of woman-haters to be born?

While that is an impossible question to answer, what is not in doubt is that the rise of trolls has mirrored the growing numbers of women willing, and eager, to be heard. Such attacks could be seen as the shadow cast by their heightened authority and visibility. Nor, sadly, are all trolls men. Women have been shown to be every bit as malevolent. And while political views are often the trigger, jealousy is probably the most common motive, be it of the commentator’s wealth, talent, status or intelligence.

It would seem that, even though women are heads of state, perform brain surgery and run international businesses, some men think they should not utter a word in public. They would probably think purdah was not reclusive enough. It is possible, I suppose, that these individuals do not fully recognise their anger and prejudice. Just conceivably, they might consider themselves as righteous defenders of some belief or ideology. But it’s hard to credit that they are completely oblivious to their Neanderthal tendencies. Nor that they are unaware of how alarming and corrosive their bile can be. Otherwise, why do so many withhold their identity?

No doubt the trolls will not be happy until women’s voices have been silenced, and only the bellowing of the male is heard. One pities the women in their life if the views they spout online are also vented upon them. But they are probably more careful than that, in mixed company at least. It is the invisibility cloak of the internet that allows them to flourish with impunity. Like vampires, exposure to daylight would be the end of them. The problem is, the internet is not going to vanish, but is here to stay. So, one hopes, are gutsy women who refuse to be intimidated or hushed.