It has to be said. The platitude that Britain “punches above its weight” is being tested to destruction. At the moment, it seems, we couldn't punch our way out of a proverbial paper bag. The nightmare at Terminal 5 confirms our legendary reputation (Channel Tunnel, Wembley Stadium, Scottish Parliament, Dome, etc, etc) for being the worst country in the Western world at bringing mega-projects in on time, on budget and with all systems working on the day they open. And it has raised huge doubts about London's ability to deliver the Olympics.

Then there's the collapse of belief in the Government's economic competence, and a gloomy sense that we will all end up paying for the cock-ups inflicted on the banking system by the overpaid, overweening barrow-boys lording it in the Square Mile and Canary Wharf. Add to that a nationwide dismay over the seemingly unresolvable chaos on our grossly overpriced railways; and a widely held perception that, despite all the decrees issued by a succession of hyperventilating education secretaries, the majority of British children are leaving school with fewer real qualifications than before 1945; and a general feeling that our once-admired broadcasting standards have declined to such an extent that 95 per cent of what's on the telly seems designed for a target audience of brain-dead crustaceans; and, and ...

But enough! Just because T.S. Eliot told us that April was the cruellest month doesn't mean that I have to pile on the gloom. Let's look on the bright side. After all, the trees are in bud. There are lambs and daffs lighting up the countryside. A survey last week may have placed Britain beneath such nonentities as Luxembourg, Monaco and San Marino in the rankings of “stable and prosperous countries”, but I'm not emigrating to Monte Carlo and I doubt that you are, either. So what keeps us here? Well, I've drawn up a list of Five Great Achievements that Britain has managed in my lifetime. See if you agree.

1. Goodbye, hated tower blocks

Three cheers for people power! It has not only halted but begun to reverse the detested high-rise housing policies imposed by “we know best” architects and town planners in the 1950s and 1960s. There are still dozens of inhumane inner-city estates waiting for a friendly wrecking-ball. But the tide has turned. Domestic architecture is again grounded in what ordinary folk want, rather than the chilling theories of haughty visionaries who wouldn't dream of living in a tower block themselves. Combined with the regeneration of once-crumbling industrial cities - Manchester, Newcastle, Birmingham and now Liverpool - the trend has rekindled a real pride in our urban landscapes.

2. Hello, proper food

When I recall what my parents fed me when I was young - bread and dripping, fish coated in more than one's own body-weight of batter - I'm amazed that I'm still here. Love or loathe big supermarkets, you can't deny that the British have revolutionised their tastes in food. And cosmopolitanised them, too. The range of high-quality culinary experiences available now, even in relatively small towns, is exhilarating to anyone brought up in an era when the eating-out options for ordinary families comprised chippie, Wimpy or greasy spoon.

3. Irish peace

I was a teenager when the Troubles started in Northern Ireland. There were times - after Bloody Sunday in 1972, or during the hunger strikes in 1981 - when I felt (along with nearly everyone else) that this seemingly unresolvable clash of loyalties and aspirations would remain a festering, shaming sore in our national fabric for ever. Today, the barricades of Belfast and Derry are tourist attractions. I see that historians have already begun arguing about which politician or sectarian leader can claim most credit. But I believe it was an unswerving desire for peace and normality on the part of the Province's long-suffering citizens - the feistiest folk on these assorted isles - that prevailed in the end. Ireland, north and south, is an astonishingly inspiring place. Now, after hundreds of years of bloodshed, we can all enjoy it without fear. It's our generation's finest political achievement.

4. Countryside matters

Despite all the fears about swaths of Britain disappearing under housing estates and out-of-town malls, our doughty conservationist bodies have been remarkably successful at preserving our rural landscapes and spectacular coasts. That's a vital achievement - because it is landscape, more than anything, that nourishes and defines the soul of a nation. And thanks to some far-sighted lottery awards that landscape is now opened up - via long-distance paths, cycleways and lovingly restored canals - as never before. We should all get out more and enjoy it.

5. Tolerance and its rewards

The Britain of my childhood was a bigoted, blinkered place - still derisive or suspicious of non-whites, still locking up homosexuals for being true to themselves, still censoring films, plays and books judged to overstep boundaries determined by Victorian prudes. We can and should have a vigorous debate about how many new immigrants Britain needs, or can absorb. But what cannot be denied - except by the Little Englanders who seem to control certain newspapers - is that the ethnic diversity that is now so much a feature of Britain's big cities has enormously enriched our cultural life, and largely been achieved without the ugly racial clashes evident in the US or France. Britain can now credibly claim to be as tolerant and as vibrant a multicultural society as exists on this planet. In my book, that's a cause for celebration, not lament.

What do you think of my Five Great Achievements? Superficial codswallop? Dangerous twaddle? Do let me know! In the spirit of open-minded tolerance that I have just applauded, I may even print the more entertaining responses in a week or two.

It's all a conspiracy, I tell you

The coroner may be right to deride fantasies about the “murder” of Diana, Princess of Wales. But the notion that the conspiracy theorists will shut up, just because a bloke bearing the quintessential Establishment moniker of “Lord Justice Scott Baker” tells them to, is as fanciful as the theories themselves. The paradox about conspiracy theories, whether they concern JFK, Jack the Ripper or 9/11, is that the more the authorities shout “bonkers”, the more the theories flourish. Rational appraisal of the facts rarely plays any part in this process. I've been dipping into the new Chambers Dictionary of the Unexplained, a brilliant compendium of bizarre “occurrences” that apparently sane people claim to have seen or heard over the centuries. Despite Scott Baker's strictures, I fear that what happened in that Paris tunnel 11 years ago has now entered those seemingly indelible annals where yetis, poltergeists and flying saucers roam.

Poor show

Theatrical types hate being labelled as “whingeing luvvies”, and most aren't. But Kevin Spacey has not best served his own theatre, the Old Vic, or theatreland generally with his petulant attack on the BBC for showing TV talent contests that identify new stars for West End musicals. “Are they going to do one about a play?” he asks. Of course not - for the same reason that Match of the Day televises football and not croquet: mainstream TV covers mainstream interests.

Even so, TV shows such as Any Dream Will Do lure millions to live theatre. Some of those newcomers will go on to sample the serious dramas that Spacey puts on. But even if they don't, the unarguable fact is that big musicals drive the West End's entire economy. If Spacey can't see that, perhaps he should go back to Hollywood - where, of course, populism is never allowed to override integrity.

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