[TheCipher]

An EMP would not just take down the power grid. It would destroy the transformers essential to the grid’s operation. Probably at least a year to begin a fix, years to get things back to normal. Although “normal” would never be normal as we think of it.

You just have to take out 9 specific HV transformers during peak usage to cause a coast to coast blackout. These are not guarded. All it takes are 9 sleeper agents to act at the same time. I'd be suspicious of some of these 30 year old "college students" at universities near these transformers.

Here is a Congressional Research study done on the security of the power grid back in 2014 :

Physical Security of the U.S. Power Grid: High-Voltage Transformer Substations

[Kartographer]

The standard answer here seems to be:"Y2K didn't happen so this can't happen."