With an EMP you wouldn't need to crash the economy in advance and you wouldn't need to orchestrate race riots in advance like they are doing, an EMP would take care of both.
I predict there will be IED’s and car bombs used during and after the riots and there will be bombings against banks and other financial institutions. These bombings will be tied to foreign terrorist working with the militants instead of just domestic terrorist like the Weather Underground, which would make them acts of war.
With an act of war, federal troops will be in the streets under the presidents control, not national guard troops under the govs. control.
It all depends on how they want it to go down, which probably depends on what they think they could get away with. EMP might be a last resort.
I don’t know if we have enough federal troops in the country to take over the whole place. Martial law in just the major cities might not be enough to stop an election or to carry out a complete revolution.
If they wanted to do the complete revolution against an armed citizenry they’d have to use something like an EMP to cut off communications and get rid of the actual government in place at the time.
It depends on how quickly and how radically they want to do this, as opposed to a slower, sneakier approach.
In any event they’ve got lots of options, and we’ve got a hostage government taken over by a foreign enemy combatant who’s had 3 years to disable all the systems intended to protect us from him, so there’s nobody to protect us from ANY of these scenarios.