At times over the past month, the Duke and Duchess of Cambridge’s official tour of Down Under has felt like watching an extreme sportsman trying to beat his personal best. We’ve had culturally aware photo opportunity after culturally aware photo opportunity, cute after cute and, of course, outfit after outfit.

Day after day of carefully coordinated brights, politically relevant details and thematic ensembles designed to reflect whatever yacht she’s manning or rock she’s inspecting – there’s no escaping the fact that the Duchess of Cambridge’s wardrobe is something akin to a military operation. It’s the sartorial equivalent of shock and awe. There’s probably a secret room in Kensington Palace where people push little Kate dolls around a map with sticks.

"Her wardrobe is a military operation. There's probably a secret room in Kensington Palace where people push little Kate dolls round a map with sticks"

And that’s why it’s so endlessly fascinating. Why people who otherwise wouldn’t really be that bothered become suckered into conversations about what she’s wearing. Because there’s a strategy at work here. Because, while recognisably wearing ‘fashion’, Kate Middleton is not remotely ‘fashionable’. And before I am taken to the Tower to be summarily beheaded, that’s an observation, not an insult.

Being fashionable isn’t about following trends slavishly or being able to recognise a certain designer’s handiwork from seventeen paces. It’s about tapping into a mood and mode of dressing that prevails at any one time. And Kate Middleton doesn’t do that; she doesn’t dress like a real person.

That’s precisely the point, of course, because she isn’t one. Kate Middleton’s wardrobe speaks of a highly specific sort of ‘First Lady Dressing’, one rooted in an age where women matched their gloves to their pocketbooks and always wore hats. Admittedly, it was a far more glamorous age. But it’s the Queen’s era, not that of a 32-year-old woman in 2014.

It’s Princess Margaret in a hat that looks like a sleeping cockatoo. It’s Jackie O’s pillbox and skirt suits. It’s almost Thatcher – and it already felt retro when she did it in the 70s. It’s so formal and self-consciously ‘ladylike’ that it’s practically an air hostess. Or rather, it’s what air hostesses are modelled on. And it’s what normal people only wear to weddings.

Kate Middleton’s wardrobe, while sourced from some of the finest designer labels in the world, strays into that sketchy category known as ‘occasionwear’. This phrase is normally only applied with reference to mothers of the bride and sold out of boutiques in well-to-do market towns with names like ‘Suzanna’ or ‘Felicity’.

It’s a heavily stylised and nostalgic look that forms the cornerstone even now of your average wedding dress code. Which is odd in itself, because it proves a certain truism: that to feel and look smart, we subconsciously turn to the styles of yesteryear because our own wardrobes have slouched so far from those starchy buttoned-up days. Kate Middleton, adopting that truism as her entire wardrobe ethic, looks like the woman in the Shopping with Mother Ladybird books – and she was dressed like our parents’ parents.

It’s pointless to debate whether the Duchess of Cambridge should or should not be following trends or dressing her age. There’s no moral imperative to do either, and it’s arguably a waste of breath. But it’s of some socio-political interest that she (or her team, at least) chooses to set herself apart from her future subjects by dressing in a way that feels so alien from our own quotidian. It’s like she’s dressing to sit for an official portrait every day - which isn’t that far off the mark, given she’s one of the world’s most photographed women.

Royals have always done it: Louis XIV had a pair of red soled shoes long before Christian Louboutin was a twinkle in anyone’s eye; Elizabeth I decreed that no-one’s ruff should be bigger than hers; Roman emperors forbade the wearing of purple by anyone not of the imperial household.

In modern terms, it’s appearance politics of the Lady Gaga school. The mask doesn’t slip. We’re unlikely ever to see Kate Middleton looking tired in a pair of jogging bottoms, even as our own day-to-day code veers ever more toward the casual.

Monty Python’s medieval peasants knew who the king was ‘because he hasn't got shit all over him’. We will know Queen Catherine because she'll be the only person still wearing a coat-dress and matching hat.

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