Where does the NHS row go next?
Even by the standards of recent weeks, David Cameron's attack on the NHS in his conference speech at Llangollen was startling.
This is what he said: "I tell you - when Offa's Dyke becomes the line between life and death, we are witnessing a national scandal."
Offa's Dyke is only a few miles from the Welsh Conservative conference in Llangollen and the clear implication of what he said is that if you're on the English side you're less likely to die
The comment came soon after the Health Secretary Jeremy Hunt told me he believed the Welsh government's attitude on mortality rates in the wake of the Mid Staffs scandal was "morally indefensible."
It's a remark which was followed very quickly by a response from Welsh Labour saying that if you listened to Jeremy Hunt for long enough you'd think Mid Staffs happened in mid Wales, rather than in England.
Labour also pointed out that Llangollen is only a few miles from Offa's Dyke, and on the other side of the border the Shrewsbury and Telford Hospital Trust is considered high risk in the English NHS.
The question is where does this row go from here, with another year to go until the general election.
Probably the oddest moment of the day came when the Labour MP Ann Clwyd was given a standing ovation on the conference floor for her work exposing problems in the NHS.
It was a provocative gesture, matched by the equally provocative gesture of inviting the UK Health Secretary Jeremy Hunt to be the opening speaker in the first place.
It's all part of what a senior member of the party in Wales told me was an "aggressive" strategy in Llangollen.
Before this conference, I'm told that Carwyn Jones had privately written to David Cameron saying that political knockabout was all well and good but what he was saying about Wales was unacceptable because it was destabilising the NHS.
I'm also told the response from Downing Street was robust.
In other words, what is being said publicly is being mirrored in private correspondence between the UK and Welsh governments.