On another level, I was at a conference recently and heard directly from those within the utility industry how many cyber attack attempts they are getting a week--most very sophisticated and thought to originate from foreign sponsored sources/governments. They are getting so many that they are almost (in my perception) numb to it and take it as an expectation.
Those attackers only need to be successful one time, and no messy fingerprints as the way a nuke/EMP would be.
I was thinking along these lines myself.
An EMP attack would be bold and in your face. It would also provoke a powerful response. However, “the death by a thousand cuts” would eventually bleed out the victim before they’re aware of it. The communists in the Frankfurt School pioneered the effort; the Islamists are using the strategy by setting up schools within the enemy camp and slowly establishing shari’a. I fear that kind of subversion far more than a nuclear blast over Kansas.