If you've had an eagle eye on the Duchess of Cambridge's wardrobe in Australia, you'll have paid special attention to that Zimmermann broderie anglaise frock – one of the stand-out looks of her trip. Yes, it's the most age-appropriate outfit she's worn recently, but it also achieves something Kate is not best known for: it taps into a major emerging fashion trend.

There's been something in the air over the last week: the red carpet has been a whitewash. It began with Rihanna at the MTV Movie Awards, impossible to ignore in an almost holy-looking long white gown – worn open over a very unholy white leotard.

Stylist Kate Foley, ex-buyer for Opening Ceremony, gave white her professional approval at a book launch on 15 April. Her version, with heavy fur shoes and a closed denim jacket, took the seasonal lightness out of the skirt and made it a fashion piece. This is a New Yorker's way of wearing a colour that the rest of us associate with summer barbecues and beach cover-ups.

At the Tribeca Film Festival, where the red carpet seems to be in action from morning to night, one colour has popped up again and again, in its boldest forms. America Ferrera wore an unnamed dress with a snowy white skirt; Maggie Grace paired two stark KaufmanFranco pieces with yellow accessories;  and Estelle chose a graphic Proenza Schouler pleated dress.

Finally, Anna Camp unwittingly chose a laser cut dress (by London label Self-Portrait) similar to the Duchess of Cambridge's Zimmermann version – it's either fashion telepathy, or white just feels so right for right now.

So what's the big deal with white? It's a blank page and yet it makes a strong statement; that's why it's a favourite of House of Cards powerhouse Claire Underwood. An icy white dress speaks of a woman who wants your attention and is not remotely worried that she'll spill her lunch today. And that's some serious confidence.

Below, click through all the best looks we've spotted this week.