> The war in Ethiopia is often cited as the immediate cause, but people have always managed to farm through wars, usually at least enough to avoid the Ethiopian situation.

This isn’t true. See the Thirty Years War. There have been many wars in the past that have led to mass starvation by making the work of agriculture impossible. See also the depopulation of Sichuan during the Ming- Qing transition.

Separately the Ethiopian war was subsidised by western food aid and other aid to the Dengists.