Nuclear Missile Silos are not targets. They would be empty before an enemy ICBM could get there.

Large Cities of strategic importance (major SeaPorts, and AirPorts), and Every major crossing of the Mississippi would be targeted, and every major Railway junction. The Point of the Attacks are to make it hard for the US to operate, by disrupting commerce, and transportation, communication really cannot be stopped.

Striking population centers, while a tempting target, is not that important, use 12 nukes to strike the 12 most populated cities, kill millions, or nuke our means of transporting food and kill almost everyone (rather the hunger riots would make us kill ourselves, it would only take about 7 days for people to begin panicing and swarming like locusts across the countryside). Remember Kill people and the needed resources go down while the supply of resources remains high… kill the supply while keeping the demand high (by not killing that many people) and you will more quickly deplete the supply cache in high population cities.

EMP effects do not last long enough to have a long term effect. within a week most electronic devices would be working fine, few would suffer lasting damage, and the persisting electrical noise would dissipate much quicker than movies and books make it seem.