By the desensitising standards of routine American gun violence, yesterday’s shootings at Virginia Tech university were shocking only in their scale. Over more than 20 years, Americans have got grimly used to a ritual that plays out on the cable news every few months. The initial news is sketchy, reports of shots fired at a campus or in a schoolyard. Then, the first confused images of students running terrified from classrooms, black-clothed Swat teams gingerly pressing into doorways; the press conference in which some dazed school principal or university president mutters the first incomplete details, with casualty estimates and emergency phone numbers for worried relatives to call.

Finally, as the horror gradually dawns in its fullness, someone finds some photograph of the gunman, pulled from a high-school yearbook or holiday. Sometimes he is a fresh-faced, American-as-apple-pie-looking young man who friends say would never harm an insect. Other times, in that first image, the brooding face is already a sad window into a soul that is well on the way to its ultimate destination of murderous and suicidal mayhem.

It’s so familiar you could write the script yourself. Only the names change — Jonesboro, Columbine, Lancaster County and now Virginia Tech. And the numbers.

Yesterday’s death toll of more than 30 handed Virginia Tech, a proud college with a strong academic record and a famous sporting pedigree, the unwanted title of worst shooting in US history. There is something slightly unsettling about the way news reporters seize on these landmarks with the kind of statistical excitement with which you would announce a new sporting record. You can’t blame them. It is the only thing that really distinguishes one of these events from another in the public’s mind.

And the truth is that only an optimist would imagine Virginia Tech will hold the new record for very long. Surely in a year or two the news networks will be replaying the same footage from another college, with only the numbers different.

Perhaps of all the elements of American exceptionalism – those factors, positive or negative, that make the US such a different country, politically, socially, culturally, from the rest of the civilised world – it is the gun culture that foreigners find so hard to understand.

The country’s religiosity, so at odds with the rest of the developed world these days; its economic system which seems to tolerate vast disparities of income; even all those strange sports Americans enjoy – all of these can at least be understood by the rest of us, even if not shared.

But why, we ask, do Americans continue to tolerate gun laws and a culture that seems to condemn thousands of innocents to death every year, when presumably, tougher restrictions, such as those in force in European countries, could at least reduce the number?

The truth is, not all Americans do oppose such measures. The US of course, is a vast, federal nation, with different laws and cultures in different states. In Virginia, scene of yesterday’s shootings, they passed a law a few years ago that did indeed restrict gun purchases – to a maximum of one per week. In the neighbouring District of Columbia, on the other hand, the law bans the possession of all guns.

DC’s draconian measure highlights one reason tighter gun control is difficult in the US. The federal courts recently ruled that the ban violates Americans’ right to bear arms, as protected by the Second Amendment to the Constitution.

But the constitutional question is not, in fact, settled. The final legal status of gun control rests at least in part on the composition of the Supreme Court and can, and has, changed, over the years.

Those on the Left like to think that the reason guns remain so available lies with the famed power of the National Rifle Association, the body that promotes the interest of gun owners. The NRA is deemed to be so influential that it can force members of congress or state representatives to support permissive gun laws, for fear of losing the association’s useful financial support at election time.

But this is overblown. The NRA is certainly a powerful body but cannot on its own outweigh the views of millions of ordinary Americans.

The simple truth is that Americans themselves remain unwilling to take drastic measures to restrict gun availability. This is rooted deep in the American belief in individual freedom and a powerful suspicion of government. Americans are deeply leery of efforts by government to restrict the freedom to defend themselves. A sizeable minority, perhaps a majority, believe the risk that criminals will perpetrate events such as yesterday’s is a painful but necessary price to pay to protect that freedom.

The sheer scale of the carnage yesterday may after all make the Blacksburg killings truly unique in American history. That will doubtless lead to more self-examination and perhaps calls for new restrictions on firearms. But it won’t change America’s deep-rooted and sometimes lethal commitment to its own freedoms.

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