@cstross Mutual ruin is the expected outcome of wars.
The US is the Oil Empire; people who are not in the US tolerated that and the consequent post-war order because it was, by and large and on the whole, beneficial. Open trade, freedom of the seas, all that stuff.
An authoritarian US is not beneficial and the exceptionalism that went into supporting an expectation that the US would not go there is stone dead. Everyone else now wants to end the Oil Empire even without the food security issues.
@cstross My expectation is that the US is going to collapse its economy committing genocide against Iran. Once the US economy goes down, a period of global rearrangement happens, only it's going to be happening in a context of repeated famine as the weather gets more angry than hitherto. (Israel does not survive US collapse.)
I think it's also notable that there is no way out of this that doesn't involve "and a miracle"; none of the better scenarios are plausibly materially possible.