The consensus at Ian's Bakery, where the scones seem to take their inspiration from the Rocky Mountains framing us, is that the police should have shot back. Footage of the riots in England played for days on the news - a rare penetration of British news that isn't about the royal family into mainstream American consciousness.

A woman in London whose shop had been ran­sacked was shown pleading for police protection. The response was unanimous: give her a gun. "What the hell they doin'?" asked one man. "Shoot 'em." Admittedly this was the Mid­west, where the baker shoots bears in his spare time and hands out the roasted meat free with the breakfast burritos. Still, these people reflected a healthy dose of American opinion that simply would not have put up with what they were watching. They couldn't believe the shop owners were not allowed to defend them­selves, and shook their heads in amazement when I said the police were banned from shooting, too - not even plastic bullets or water cannon.

Another man, a retired army officer studying post-colonial literature - no honky-tonk cowboy - racked his brains to recall disorder of this sort in the US and came up with the Watts riots of 1965. There has been plenty of rioting in the US since then, but it largely occurs around colleges and in poor inner-city areas, so he had not noticed it. The reason why is evident in the suburbs, where I'm writing this: mile upon mile of tasteful clapboard, a low-density sprawl that the writer Eric Schlosser has described as "the architectural equivalent of fast food".

Over the past 20 years, immense subdivisions of small towns have sprung up all over Colorado: "the houses seem not to have been constructed by hand but manufactured by some gigantic machine, cast in the same mould and somehow dropped here fully made. You can easily get lost in these new subdivisions . . . without ever finding anything of significance to differentiate one block from another - except their numbers. Roads end without warning, and sidewalks run straight into the prairie, blocked by tall, wild grasses that have not yet been turned into lawns."

Here is where the white people live, segregated from black America. More than half of America lives in suburban areas; in Europe, two-thirds of us are urban. In tidy houses in neat suburbs, policed by small private armies of security guards and homeowners' committees, white America insulates itself from black.

House rules

With the new suburbs come rules: rules about the size of your trash can, the number of Christmas lights you may display, the colour of your curtains, the weight of the family dog. Professor Setha Low, a former president of the American Anthropological Association, says these rules entrench middle-class values. "Middle-class families imprint their landscapes with 'niceness', reflecting their own landscape aesthetic of orderliness, consistency and control," she observes in Behind the Gates: Life, Security and the Pursuit of Happiness in Fortress America.
This homogeneity in effect excludes ethnic minorities. "Racist fears about the 'threat' of a visible minority, whether it is blacks, Latinos, 'Orientals', or Koreans, are remarkably similar. This is because many neighbourhoods in the US are racially homogeneous. Thus, the physical space of the neighbourhood and its racial composition become synonymous."

You can gate without putting in gates - property prices, residents' associations and just knowing one another's business act as effective barriers to outsiders. "Quiet laws" and indirect economic strategies limiting the minimum lot or house size, cul-de-sacs that allow for easy monitoring of who is where and social regulations complete the separation. In major metropolitan areas of the US, half of all new housing is built and sold as part of a collective regime, with privatised rubbish collection and security, and covenants regulated by governing bodies. One man was fined because his car leaked a spot of oil on the street. A woman was threatened with expulsion for kissing her boyfriend in the driveway. I may not hang out any washing, nor can I leave the rubbish bin out except on Fridays.

The zenith of this "nice, happy" American suburban living is the physically gated community, a "purified" environment where outsiders can be spotted immediately. A third of all new communities in southern California are gated, as is a similar proportion around Phoenix, Arizona, in the suburbs of Washington and parts of Florida. In Tampa, Florida, four out of five home sales valued at $300,000 or more are of prop­erties in gated communities. They come with gates, swipe cards and tight security. And they largely isolate the white middle and upper classes from poorer blacks.

Hurricane Katrina in New Orleans six years ago was an eye-opener for middle-class America. One Midwesterner bemoaned to me the television pictures of all those people "sitting on their fat black asses" and waiting for government help. A more liberal man noted that it was a "wake-up call" to white America, which did not normally see inside the black inner cities.

In the US, as in Asia, Latin America and South Africa, the separation and gating of communities is an accepted symbol of vastly unequal societies in which the winners must be physically protected from the losers. Figures from the US Economic Policy Institute show that, in 2009, the median net worth for white households in America was $97,860 (a fall of 27 per cent in five years); for black households, it was $2,170 (a fall of 84 per cent over the same period).

Black America is finding ways to fight back, with a trend towards flash-mob attacks in upscale department stores and the restaurant districts of cities such as Philadelphia and Chicago. On 29 July, two dozen youths, one as young as 11, beat up and robbed bystanders in central Philadelphia. The city has imposed a weekend curfew of 9pm for minors. In Chicago in June, up to 20 young men violently robbed people in Streeterville, a usually trouble-free area dominated by upmarket shops and skyscrapers. These forays into middle-class white American territory are rare, but becoming less so.

In Europe, we segregate less - and we are less unequal. Median total wealth per household in the UK, according to last year's National Equality Panel report, is £21,000 for black Africans, £76,000 for black Caribbeans and £221,000 for white British. For Bangladeshis, it is £15,000; for Muslims, £42,000; for Indians, £204,000. The figures are not directly comparable with those for the US, but the relative poverty levels are: black America is far poorer relative to white America than black Britain is to white Britain.

Not that we have anything to be smug about. The Equality Panel reported that, by 2008, the UK had the highest level of income inequality since soon after the Second World War. And the average household wealth of the top 10 per cent, at £853,000, was nearly 100 times higher than the wealth of the poorest 10 per cent, at less than £9,000. These figures include property, savings, cars and pension rights.

Geographical segregation, too, is increasing in the UK, not just between north and south, but within regions and local authorities. The north might be far poorer than the south - household wealth in the south-east is 1.7 times that in the north-west - but the variation in wealth is higher in the south and especially stark in London. There is some evidence that the social marginalisation of poorer wards is increasing all over England, with the gap widening between these areas and their locality in terms of health, education, employment and income.

Urban paranoia

The degree of geographical segregation and privatisation of public space in the US will never be matched in England. First, we do not have the space. As John Micklethwait and Adrian Wooldridge point out in The Right Nation, the US has enough land to give every household an acre and still populate only one-twentieth of the continental United States (excluding Alaska). Second, we do not have the same culture of privatisation, even though our security-patrolled shopping centres mirror the trend and gated living is becoming more popular. The research is mixed as to whether it makes people feel more secure; some say their segregated communities make them feel safe, others have become more paranoid about strangers.
So, without segregation and without guns, what is to be Europe's solution to civic unrest in the face of soaring economic inequality? David Cameron has reached for an answer in the shape of Bill Bratton, the former New York City police chief hired to advise the Prime Minister. Bratton is associated with falling crime rates in US cities due to a "zero-tolerance" approach that Cameron has said he will adopt in the UK. He may be disappointed.

The economist Steven Levitt has conducted research suggesting that the decline in New York's crime rate had more to do with rising numbers of (armed) police, a higher prison population and the legalisation of abortion than Bratton's methods. The drop began before Bratton was appointed, Levitt argues, and other cities that did not employ his style of policing experienced similar falls in crime, once police numbers were taken into account.

Bratton may be a good headline, but he is not the solution. That leaves Cameron with the options of spending more on police and prisons
to match incarceration rates in the US, where black people are three times as likely to be jailed as in England and Wales. Or he could tackle inequality: in inherited wealth, in employment, in wages, in opportunity. But that, as Labour can painfully attest, is the hardest headline to win of them all.