That's the first line of an article in The Sun called "VANCE SHAME/Fury as Trump’s No2 JD Vance mocks UK for ‘not fighting a war in 30 years’ – forgetting Afghanistan & Iraq."
That calls our attention to something Vance said on Fox News: "If you want real security guarantees, if you want to actually ensure that Vladimir Putin does not invade Ukraine again, the very best security guarantee is to give Americans economic upside in the future of Ukraine. That is a way better security guarantee than 20,000 troops from some random country that hasn't fought a war in 30 or 40 years."
I don't know if that "random" refers to the UK, but apparently some people in the UK are hearing it that way. And the UK is hardly a random country. But "random" is bandied about humorously these days. In America. Do the Brits know that?
Insulting him back, the random Brit who is the source of this quote doesn't seem to know that Americans don't say "wind his neck in." The effort at an insult strikes me as funny because, not being used to the phrase, I'm forced to try to picture it concretely.
The source of the quote is a Former Veterans Minister who served in Afghanistan, and the full quote is: "Vance needs to wind his neck in. Show a bit of respect and stop making yourself look so unpleasant."
Vance looks especially unpleasant in my mental image, where he has an extremely long and thin neck attached to a fishing reel.