@farmerman,
Well, i don't know enough to attempt to speak authoritatively. I do believe that it would be possible to recover potatoes, even if a commercial disaster descended upon Idaho or Prince Edward Island.
The vineyards of France and Italy got nearly wiped out at the end of the 19th century. They rebuilt their vineyards with cuttings brought from California. It kind of beggars the snottiness of those who allege that French or Italian wines are superior to California wines, but for me, the point is that for whatever the disaster may be for the individual grower, the crops can come back.
In Ireland the potato blight of the mid-19th century destroyed the potatoes everywhere but in Kerry. Repeated attempts to recover the potato crops by using cuttings from Kerry failed, but someone made one more try, and the potato recovered in Ireland. Kerrymen have become the "Polacks" of Ireland--lots of "dumb" jokes about Kerrymen. Maybe that's why--resentment.