Americans are violent. Surprised?

The US Attorney-General, Janet Reno, floated the idea of stricter gun control last week after yet another American set out to massacre his fellow-citizens, this time in a Jewish community centre in Los Angeles. The gunman, Buford Furrow, gave himself up after wounding five people at the centre; he has also been charged with killing a Filipino postman. Furrow is a self-declared white supremacist, a neo-Nazi who taught hand- to-hand combat at an Aryan Nations compound in Idaho, which at first sight sets his actions apart from other multiple shootings in the United States.

These include the massacre at a high school in a suburb of Denver in April, when two teenagers murdered 12 fellow-pupils and a teacher, and the murders in Atlanta last month by a man who had lost thousands of dollars in day-trading on the internet. The motives in these horrible events are very different and the earlier cases ended with the suicides of the perpetrators. While Furrow made no attempt to kill himself, he faces the death penalty if he is convicted in a California court - a reminder that the American judicial process has not progressed, in 38 of its 50 states, beyond biblical scenarios of revenge.

Sixty-eight people were executed in the US last year, which seems a relatively low figure until you consider that the enthusiasm of individual states for judicial murder is hampered by a lengthy appeal process. More than 3,500 prisoners were on death row at the end of 1998, fighting rearguard actions to save themselves from lethal injection or the barbarity of the electric chair. More than 500 have been executed since 1977, when the death penalty was reintroduced, ironically at a time when other countries were going in the opposite, abolitionist direction. Indeed the US now finds itself in a select group of four nations - the others are China, Iran and the Congo - which account for 80 per cent of executions in the entire world.

These shameful statistics weaken the position of the American government when it seeks to intervene on human rights issues in countries like, er, China. They also demonstrate the extent to which violence is endemic in the US, from top to bottom. The day after the Denver shootings, a bill to relax controls on the carrying of concealed weapons was withdrawn from the Colorado legislature, on grounds of timing rather than a sudden revulsion against the constitutionally protected right to bear arms. And this is the heart of the problem: not just that far too many Americans own guns, but a cast of mind which refuses to characterise violence, and the means to perpetrate it, as unequivocally evil.

On the contrary, American culture adores violence, whether it is in the form of movies or computer games or even foreign adventures like the Gulf War, as long as very few of its servicemen or women get killed. President Clinton got it wrong when he singled out TV violence and the internet as possible causes of the Colorado murders, but only because he failed to understand that their output reflects a malaise which existed long before such relatively modern inventions. The US is built on myths of violence, with two of its favourite innovations, the Western and the gangster movie, only recently succumbing to more realistic interpretations of what their heroes actually did. Indeed the settler culture of its Western States is based on the violent appropriation of land, and a defence of that theft which necessitated the bearing of arms.

This has somehow been elevated into a principle which allows even people with a record of mental illness - Furrow was treated in a psychiatric unit in Seattle only last year - to get access to lethal weapons. Even the fact that two of their presidents have been murdered in office and another, Ronald Reagan, seriously wounded, has not persuaded sufficient American voters that their romance with the gun can no longer be tolerated. On the contrary, leading politicians themselves display a dismaying readiness to turn to violence as a first resort, wantonly launching air strikes on countries which obstruct US foreign policy objectives.

It is this ambivalence, as much as the glaring gap between the rich and poor, which makes the US so vulnerable to these grim assaults. Of course no country is immune, as we can see from a knife attack on three people in Leicester last week. But when successive governments legitimise violence, and the entertainment industry glamourises it, it is not surprising if slightly unhinged people come to regard it as a solution. Celluloid mobsters and serial killers are the relatively benign face of a culture whose dark side is judicial murder, brutal state-run penitentiaries and a population which goes in fear of lethal attacks by aggrieved fellow citizens.