Yeah the attack on miners and whitelisting blocks is definitely a thing but a topic for a whole new post.
That being said I'm highly skeptical they can pull it off.
The closer they get to victory the more likely it is that the real Bitcoiners will stand up and delegate their hashpower to a node that refuses to obey the sanctions.

There's also a very strong chance that they push through laws at first that tighten the clamp, but then lose lawsuits later that force them to roll it back. Either that or they just get rolled back when the blue administration turns red.