The campus shooting phenomenon in the US would have lost much of its power to shock by now if it weren't for the fact that the perpetrators keep ingeniously introducing new twists. Last October, it was an Amish school, of all places; in 2005 it was a school on a Native American reservation. On what was almost exactly the eighth anniversary of Columbine - hitherto a one-word thumbnail for this whole family of atrocities - the 32-body-count shooting at Virginia Tech has an uncomfortably competitive flavour. The man who killed himself all too late in the day in Blacksburg, Virginia, claimed more than twice as many victims as Dylan Klebold and Eric Harris did at Columbine high school in 1999. Though "Virginia Tech" doesn't have the same ring as the punchier "Columbine", you wonder if this new shooter wasn't making a bid to update the cultural lexicon - to coin the new byword for random campus violence.

While the killers continue to improvise, the media aftermath is numbingly ritualistic. We ask: why do these rampages keep happening, why primarily in the United States, and what is to be done? The answers vary, but they are universally unsatisfactory.

Why do they happen? If it does not sound too tautological, campus shootings keep happening because they keep happening. Every time one of these stories breaks, every time the pictures flash round the world, it increases the chances that another massacre will follow. In the main, all of these events are copycat crimes. Campus shootings are now a genre, much as, in literature, campus-shooting novels are a genre, one of whose entries I am guilty of writing myself. They are part of the cultural vocabulary, and any disgruntled, despairing or vengeful character - of any age of late, since grown-ups now want in on the act - now has the idea of shooting up a campus firmly lodged in his brain.

I do not believe that the choice of schools or colleges for the pursuit of grievance or, often, for the staging of what I call "extroverted suicide", is arbitrary. For most of us, school and university are the seats of profound and formative emotional experiences, and the psychological power of these locales does not necessarily abate with age. Only last month I had reason to walk down the hallway of an elementary school in the US, and the lockers, lino and acrid chalk-dust smell sent my head spinning with memories, not all of which were pleasant. I felt claustrophobic, smothered, actively grateful to be spared the tyrannies of Mrs Townsend's home room, and relieved to get out. In fact, I couldn't believe I was allowed out of the door without a pass.

For a lucky few, school and college are where we first distinguish ourselves. But for the majority, they are the site of first humiliation, subjugation and injury. They are almost always our first introduction to brutal social hierarchies, as they may also sponsor our first romantic devastation. What better stage on which to act out primitive retribution?

As for why America in particular sponsors these killings ... as I write, relatively little has been made public about the shooter in Virginia, but that won't be the case for long, which is probably as he would have wanted it. Anonymity is the last thing most of his fellow campus shooters have sought.

Time was that appearing in the newspaper for doing something dreadful was a fearful prospect. But Americans appear to have lost touch with the concept of shame. Now that my compatriots have eschewed the old distinction between fame and infamy for the all-embracing concept of "celebrity", all that counts is being noticed. Even posthumous attention beats being ignored.

I would far prefer that this new killer remained anonymous. Were all such culprits to remain utterly and eternally unknown, the chips on their shoulders interred with their bones, their grudges for ever private, surely the frequency of these grotesquely gratuitous sprees would plummet. One of the driving forces for most of these killers is not just to be noticed, but, however perversely, to be understood.

But you can't outlaw being disaffected or artificially force a culture to re-embrace the concept of shame. Nor do we want educational institutions to engender the paranoid, dread-steeped ethos of modern airports. Surely the only effective preventative measure is logistical. Make it harder to get guns.

How many mass killings does the American public have to witness before its government gets serious about gun control? While the source of armaments in Monday's shooting has yet to be disclosed as I write, Virginia has some of the most lax gun laws in the country. You can buy "only" one handgun per month, and criminal-background checks are not required to buy weapons at gun shows.

Nevertheless, American versions of strict gun control are so farcical that many campus shooters would still have had no problem acquiring weapons while playing by the most stringent of rules likely to be applied. Who is to say that campus shooters of the future won't be perfectly content to bide their time as a required "waiting period" between purchase and acquisition ticks by?

For America's federal government to take gun control seriously, nothing less than mass armed insurrection is required. Were the public ever to act on the principles of their own Declaration of Independence, for example - "That whenever any Form of Government becomes destructive ... it is the Right of the People to alter or to abolish it, and to institute new Government" - Congress would shut down the gun industry in a heartbeat.

· Lionel Shriver is the author of We Need to Talk About Kevin, a novel about an American school shooting. Her new novel The Post-Birthday World will be published by HarperCollins in May.