The pandemic example was just an argument that our food supply system is robust in the face of some unexpected events. What do you think could happen during non-pandemic events which could topple it?
Antagonistic relations. During COVID-19 pandemic, most nations took the "we're all in it together" stance (despite being mostly busy handling things domestically). Climate change will create lots of opportunities for war - migration pressure, resource shortage pressure, new lands being suddenly available and competed for, etc.