[cripplecreek]

If provoking confrontation is indeed the endgame, the logical next step would be trying to shut down the interstate highway system.

Short of taking out bridges its pretty much impossible and then there's the fact that it would enrage left and right alike.

[wizr]

Highways filled with cars stalled or abandoned will block many well traveled roads.

[CodeToad]

“Short of taking out bridges its pretty much impossible “

Maybe, but initially they can. Here in the snowy States we have gates they can lower to prevent access onto the freeways. I think you probably have them, too. Put a few patrols out to enforce those closures and the freeways would initially be closed. However, people might not care for the closure for too long and the few cops and DOT personnel trying to enforce the closure will be overwhelmed.