JKR has been a staunch labour supporter, she's donated. She's the world's leading, best loved children's author. She's a mother and she's political.
She's got tremendous clout.
And, best of all, she's absolutely determined to air her views publicly. We know the gender critical attitude is persuasive, because it's right. And as a clever, creative writer she puts it across perfectly.
If I was Starmer, I'd be bricking it.
If this issue can, as we all predicted, make him look like an absolute sexist twat, it's going to be brought up every five seconds.
And there's no one better to bring it up than JK Rolling.
I bet he's desperate to get her on side. And I bet she's equally determined to totally hold the line.