Insurers typically don't insure for correlated risk (natural disasters, war etc) because no insurer actually has the reserves to pay it out. Which is why water

Insurers typically don't insure for correlated risk (natural disasters, war etc) because no insurer actually has the reserves to pay it out. Which is why water damage from a burst pipe will likely be insured but water damage from a flood is unlikely to be insured, even though from a homeowner's perspective they are effectively the same damage.