Simon Kelner: High streets are closing; we should heed Mary Portas

Sometimes it's hard to believe we are beset by deepening economic gloom. Here in London, it's well nigh impossible to get a table in a top restaurant, and the department stores are packed to bursting.

On a visit to Manchester last week, it was the same story. And when was the last time you got on a flight that wasn't full? A visitor from Mars would be left to conclude that we are in the midst of an unprecedented boom. The reality, of course, is very different. Insecurity stalks the nation, and while the desire to have the sort of Christmas imagined by the John Lewis advert is powerful, there is a sense that the worst of times may be around the corner.

Nowhere is that clearer than on the high streets of Britain, where an average of one in seven shops lies empty. Enter the TV presenter, and part-time government adviser, Mary Portas, who yesterday presented her review of Britain's high streets, with 28 recommendations for retail regeneration.

Portas launched her career with a Saturday job at John Lewis, and by the age of 30 was on the board of Harvey Nichols. Her TV show, Mary Queen of Shops, followed the template of reality TV – expert goes to failing establishment, has argument with intractable owner, turns things around and returns some time later to find that things have gone back to how they were. But it clearly struck a chord with David Cameron, and Portas was called in with her bag-for-life seven months ago.

Cameron doesn't need to go very far for evidence of the worsening mood on the high street. The Oxfordshire town of Woodstock lies in the PM's constituency, and, not too long ago, had one of everything: butcher, greengrocer, fishmonger, sweet shop and a hardware store.

All had been trading in the town for many decades. And one by one they have all disappeared. Some still lie empty, and the others have been replaced by charity shops. It is a depressing phenomenon, and one that has been replicated in towns all over the country.

The government is right to be concerned. We used to be worried about the creeping homogeneity of our shopping streets – a Starbucks next to a building society next to an estate agent next to a betting shop – but now we have a more serious problem, as shoppers go to out-of-town supermarkets and leave a wasteland behind.

The Portas review should be welcomed, whatever one thinks of her conclusions (although I don't see how anyone could say that giving local authorities powers to get heavy with landlords, encouraging street markets, giving rate concessions to local businesses and forcing banks to make good use of empty properties are bad ideas).

Some of the signs of Britain's economic plight are invisible, but the gaps in Woodstock's high street are depressing, and an all-too-real reminder of a shift in our lives.