Well, the 40 mile column looks like a tremendous vulnerability. Cut it into immobile pieces using drones and anti-tank weapons and it could become a turkey shoot like the one in the first Iraq War.
But I'm beginning to think the financial weapons the world has released on Russia are going to be utterly devastating. No plastic. No wires. No credit. No capital. No cash. Queues at ATMs. That is going to gum up the entire country. How do you perform a basic transaction? How does the Russian economy even work in those circumstances?