Julia Roberts’ patronising ad is right – women will vote in secret... but not for Kamala

"Remember, what happens in the booth, stays in the booth."

Julia Roberts's advert – for the liberal Christian group Vote Common Good – has provoked an immediate backlash out here in the United States. Perhaps worse, it has become a joke amongst women, with that trite little slogan parroted across many a bar top in the shrill tones of a 1950s wife. Because that's essentially what the 30-second commercial released last week is making female voters out to be.

As two women are shown entering a polling booth, they both glance conspiratorially at one another before secretly voting for Kamala Harris. Meanwhile, the Oscar-winning actress narrates: "In the one place in America where women still have a right to choose, you can vote any way you want and no one will ever know." All together now: "Remember, what happens in the booth stays, in the booth." When, as they leave the polling centre, one woman's husband asks "Did you make the right choice?", she chirps, "Sure did, honey."

The Republican rage has been most entertaining, what with Donald Trump declaring his "disappointment" in Roberts (in time, she'll get over it) and the influential conservative Charlie Kirk declaring the advert "so gross". "She's coming in with her sweet husband who probably works his tail off to make sure that she can go, you know, and have a nice life and provide for the family, and then she lies to him," he fumed, seemingly oblivious to the fact that women are now allowed to work – on occasion even working their tails off.

Brilliantly, several Grand Old Party commentators have also declared that lying to your husband about voting for Harris "would be way worse than having an affair".

What nobody has pointed out is that there's plenty of secret ballot box action... in the other direction. Just the other day my Uber driver in LA was telling me how "sick to death" she was of people assuming that "as a black woman" she'd be voting for Harris. "It's so patronising! I actually secretly voted for Trump," the woman confided, adding that she cared more about the spiralling cost of her weekly shop than feminist ideals. Then there's the New York friend of mine – the one who has been pouring scorn over Trump for the past 15 years – who has just voted for him, again, in secret. "You're literally the only person I've told," she told me after two glasses of wine. "And you have to promise never to tell a soul."

Hey, what happens in the booth stays, in the booth.