Couple that with food prcoessing plants around the country catching fire or what have you, a military with assets diverted elsewhere, and compromised/allied political leadership in the target country....
Think of Biden as that mayor in the Colorado town in the first "Red Dawn" movie.
“Because farm equipment is down”
There was a time when farm equipment was a simple diesel engine. Those would survive an EMP almost all the time.
Modern John Deere and Cat one’s are so computerized, they will die for good with an EMP.