Every morning I walk my daughter to school. Last week the sun shone and we kicked pink cherry blossom and pretended it was confetti (she has just been a bridesmaid). The school is only a couple of hundred yards from our house but the walk is always eventful. She squeals when she sees her mates from nursery and the streets ring out with her cries of “Ardit” or “Dascha” or “Samiyo” or “Kotaro”. Her class is like a UN summit. The above are, respectively, from Albania, Bangladesh, Somalia and China/Japan. She and I, white British, London born and bred, are rare birds.

There are definite upsides to all this — her geography is great. She can also sing “One, two, three, four, five/Once I caught a fish alive” in Bengali. More seriously, she has learnt sign language (great with her deaf cousin) and the very high percentage of kids with English as a foreign language in her class mean that the staff ratio is amazing. At the expensive Montessori nursery I sent her to before, they had 15 children and three staff. At this state primary school there are a little over 20 children and four or five staff (the nursery teacher and at least three teaching assistants, one speaking Bengali and another Somali). The school does an amazing job and she absolutely loves it.

But I have had to field rather a lot of delicate questions. “Mummy, why is that lady wearing a black sheet over her head?” was an early poser. Hmm. You try explaining the finer points of Islamic dress to a four-year-old. Particularly when the majority of the Muslim mums only wear headscarves, others (mainly Somalis) long flowing robes with their faces bare, but a few are in black from head to toe with only their eyes to be seen. I tried to distract her by pointing out an African mum’s turquoise and black flowery skirt and headdress and mumbling about “difference”. More tricky was when I had to comfort her when two Somali girls (her best friends) we’d invited to her birthday party — special invitations, party bags all ready — failed to show. Cultural differences I suppose.

Every morning I feel like I am part of a great social experiment. And I am not alone. Last week Liam Byrne, the immigration minister, finally admitted that the 40% of the public who say they are worried by the levels of immigration to this country have a point. “During the 1990s the UK did change from being a country of net emigration to one of net immigration — 2.4 million people left Britain and 3.4 million came in.”

In 2005 alone net immigration to Britain was 185,000 — that’s the equivalent of the population of Swindon. In fact, since 1998 the net numbers have ranged between 139,000 and 223,000. And that’s just the official figures. Nobody is counting the numbers who come in every day on lorries through the Channel tunnel (so many that the French are opening a new Sangatte camp to help them).

Byrne claims that “with that change has come enormous economic benefits” and it is true that if you are after a Polish builder, a Slovakian nanny, an Albanian to valet your car or other super-cheap labour (Chinese cockle-pickers, anyone?) then, yes, you’re in luck. But others, including Sir Andrew Green of Migrationwatch UK, warn that as these workers begin to have children, get older or get sick, then the economic benefits to the country evaporate and in fact become a burden. And what the politicians are finally beginning to wake up to is the price that the social fabric of Britain is paying by absorbing all these new people.

Like my daughter, I too went to an inner London primary school. Back then, we sang Kumbaya rather than hymns, and our hippie teachers did away with the three Rs in favour of “creative play” in our rainbow-nation classroom. Happy days. Later I had black boyfriends and believed the world was a harmonious multicultural playground.

That view was severely shaken when I went to Chicago aged 16 to stay with family friends. I was crazy about house music — which began in Chicago. In London I wouldn’t have thought twice about going clubbing in Brixton. I wanted to go to a black club in Chicago. My American friend freaked out. “We’re not going there, you’ll get shot,” she said. Subsequent travels all over the world taught me the hard way that London was a rather special place and the colour-blind world of my ILEA childhood an exception rather than the rule.

But even here in tolerant Britain there are limits. When people like the left-wing Young Foundation in east London say that working-class whites have legitimate gripes about being passed over in favour of Asian immigrants, or Trevor Phillips, the former head of the Commission for Racial Equality, says that multiculturalism is leading to ghettoisation of different races, and when home-grown suicide bombers kill London commuters, we have to start talking about what is happening to our culture. But that is not easy.

Recently I was invited to interview Phillips on stage at the CRE’s Race Convention. When I said that as a white Londoner my daughter and I were in a minority in my local school in the neighbourhood where I have lived all my life and that that change feels weird, I was viciously attacked.

The audience of race professionals didn’t want to hear. I was dismissed as a racist and when I mixed up my hijabs with my jilbabs one race-relations worker (the irony) yelled: “How dare you talk about this when you don’t know the right terminology.”

Phillips defended me, but I’m afraid I snapped. “Look,” I said, “I’m one of the good guys in this. I want multiculturalism to work. I’m choosing to send my little girl to the local school, to try and make an unbelievably disparate community work. I could have opted out and sent her to a white, private ghetto school like many of my friends. Or moved — as many others have done — to an area with much less of a mix. I haven’t. I want to make it work.” Two Nigerian ladies at the front cheered. Bless them.

I welcome Liam Byrne’s admission that there is a problem, particularly his warning that uncontrolled immigration puts undue pressure on poor communities and on schools and housing. How do you go about improving a failing school when the percentage of kids who don’t speak English as a first language rockets from 5% to 20% in a year (as happened at a Birmingham school last year)?

This influx affects all of us. My local doctor is too busy to make a house call on a sick baby because his books are so full. The open surgery is so crammed that people queue out the door. I live a couple of hundred yards from my daughter’s school but I was lucky to get her in; in the estate opposite, immigrant families with four or five children live in two-bedroom flats.

Yellow police boards shouting “robbery” or “assault” grow like topsy in the surrounding streets and gangs of menacing hooded teenagers prowl the ’hood. By secondary school, the challenging ethnic brew is beginning to ferment, giving off a noxious smell of gangs, crime and poor life chances.

As Byrne says, it is not “racist” to have a conversation about the limits of immigration on our crowded island. It is essential or I fear the pressures on public services will sour the benign attitudes which are so special to Britain.

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