For a historical analogue check out what happened in Italy on 28. September 2003. One international line in Switzerland sparked to a tree, and got shut down, that caused a cascade where the other lines to France were overheating and getting shut down a few minutes after, and Italy didn’t manage to shed enough load in time to keep up their frequency internally, then everything shut off when it drooped low enough. Took them 18 hours afterwards to get the whole grid back online.
For a historical analogue check out what happened in Italy on 28. September 2003. One international line in Switzerland sparked to a tree, and got shut down, that caused a cascade where the other lines to France were overheating and getting shut down a few minutes after, and Italy didn’t manage to shed enough load in time to keep up their frequency internally, then everything shut off when it drooped low enough. Took them 18 hours afterwards to get the whole grid back online.