Infrastructure like this is vary unprotected in this country.
The powers to be do not want to spend the money necessary to protect it.
Most are in denial that it will happen.
There is a cost to everything, including protection. And at what level would you want this protection? Guards at every substation? Multiple redundancy and duplication of systems?
I don't know that the customers would want their cost per KWH to double or more to achieve maybe 20% reduced risk to multi-contingency disasters. Though they seem more than willing to blow their monthly budget on pie-in-the-sky wind and solar schemes.