Long before the end of New York fashion week, you begin to realise that America is indeed the cliché of its reputation: a country of hype, hysteria and a strange refusal to take a critical look at itself. How else can the extravagant praise with which virtually every fashion show here is greeted possibly be explained?

Over the past few years, American fashion has shot itself in the foot. By losing some of its best designers to Europe (Tom Ford to Gucci, Marc Jacobs to Louis Vuitton), where those designers have made US fashion approaches central to sales, it has forfeited the belief that what New York has to offer is different. This is substantiated by the fact that, led by Prada, the whole world is now giving us the sort of fashion that was once uniquely American — that is, slick, commercial and easily understood by its audience. New York is now so desperate to find someone who could lead world fashion in the way that, say, John Galliano or Alexander McQueen do that it hysterically overpraises its home-grown talent. The reality is that new talents such as Zac Posen are developing rather more slowly than expected, and that some of the labels that made America such a force in the past seem to be missing their step these days.

That said, US fashion is still the most commercially focused in the world, and it is a rare show in New York that doesn’t have at least six great commercial looks to offer. We are, of course, referring to the bog-standard dresses that will sell in their thousands in department stores across America — the sort that in England we expect to see in Topshop or Zara, but in America are considered of sufficient quality to carry a designer label. It is this lack of rigour that has caused the indigenous American product to be overtaken by more sophisticated European versions. Backed by huge advertising budgets and nationwide store commitment, the top labels give us clothes that will certainly sell, but duck their real job, which is to present us with original fashion pointing forward to new futures.

The problem lies with the consumers and the stores that serve them. The US market is the most old-fashioned in the world, but it is also so huge that American fashion floats or sinks on its domestic sales alone — its designer prices are just too high for labels to sell in any great number abroad. So, we have an inward-looking industry relying on complacent home consumers who are steeped in fashion conservatism and actively shun originality.

The results are often dire. This season, catwalk after catwalk produced pastiche fashion based on the 1950s, still America’s greatest fashion moment, and one that none of the designers can let go. But not everything was bad: the labels that put America on the map back in the 1970s are still ahead of the game. Calvin Klein, under its new design director, Francesco Costa, maintains its trademark look of total assurance through complex cuts that create the simplest of shapes. Refusing to follow America’s current craze for fussy eclecticism and wild colour combinations, the Klein label still stands for grown-up elegance.

In the same vein, Ralph Lauren gave us his own perfect elegance: pale silver, pearl and white; the discreet sheen of satin and cashmere; narrow, flattering shapes ending at mid-calf. This show was a tour de force of New York style.

Less confident this season, Donna Karan did a retake on Prada for her DKNY line (as did Proenza Schouler and many others), but recovered some of her own style for her Donna Karan label: dreamy 1950s daywear, subverted with jackets sliced open at the shoulders, net inserts everywhere and corset straps popping up all over. Evening wear saw Karan at full strength, ranging from clingy jersey to folded taffeta and shantung.

Colour was everywhere at Marc Jacobs. So was pattern and glitter and a great deal of “loving hands at home” knitting. The overall effect is of little America from happier days — the 1940s and 1950s — which Jacobs manages to make sophisticated while retaining an interesting home-made, hand-crafted quality. It’s not a look that’s easy for non-Americans to understand, but it is calculated to excite the domestic market.

If Jacobs is becoming increasingly hoedown, his running mates Michael Kors and Narciso Rodriguez are firmly city-based, with the odd nod in the direction of Florida and the Hamptons. Of the two, Rodriguez was more focused this season, with his scooped round-neck jackets, three-quarter-length sleeves and strong seam emphasis. Kors was jolly, colourful and so wearable that his bank manager must already be glowing with anticipation.

Did either of them give us fashion? No, of course not. That is not how designers make money in America. Instead, there were lots of clothes calculated to dress American women without making any demands except on their credit cards.

And so to the Brits, that sad little coda to New York fashion week that is about as useful to it as your appendix is to you. Showing in half-empty venues in graveyard slots on the schedule, totally overwhelmed by the hype surrounding the home-grown product, their fashion impact is negligible. Still, Matthew Williamson and Roland Mouret are reputed to notch up reasonable sales here. My personal view is that our designers lack the sophistication that is taken for granted here, and do themselves a disservice by showing in New York. Faced with the quality and focus of the slickest fashion industry in the world, they end up looking like country dressmakers who are saying nothing at all to anybody here. And with many of its 169 indigenous designers showing clothes that are not much better, the last thing this city needs is more mediocrity.

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