The rhetoric is pretty harmless.
The North Korean foreign minister calls Donald Trump “mentally deranged and full of megalomania” at the UN today.
Add this to “dog” and “dotard” (senile old man) and you get the picture.
Trump has had his say of course, branding the North Korean leader Kim Jong Un a “rocket man on a suicide mission”.
Were there not the potential for a serious conflict it would all be vaguely entertaining. But what is less harmless are the increasingly worrying displays of strength by both sides.
In response to North Korea’s repeated missile launches and nuclear tests, the Americans have now sent bombers close to its east coast in an attempt to deliver a clear message about the military options open to the Pentagon.
The danger here is pretty clear.
Military grandstanding can very easily lead to miscalculation or misunderstanding by one side or the other which can in turn lead to action that becomes irreversible.
That way lies disaster on the Korean peninsula that could cost hundreds of thousands of lives.
Often two adversaries threatening war have a line of communication open, either through direct diplomacy or through third parties.
The problem here is that I can’t see any back channel of communication between these two.
Maybe the Chinese or the Russians are playing a part, but it is not obvious that they are.
It is worrying that, on the face of it, the only messages being transmitted between Washington and Pyongyang are being yelled by two leaders trading abuse.