Ukrainian foreign minister Kuleba to Western countries: "We offer you the best deal: you don't sacrifice your soldiers, give us weapons and money, and we will finish the job."
Vulnerable to Russia's inability to protect it's airspace or protect it's infrastructure from internal adversaries. It's not a problem that Putin can just throw more meat at. It requires the kind of functional technical solutions that Russia has failed at beyond even the expectations of even someone as blinded by western propaganda as me.
Well, we do have about twice as much rail for twice as many people.
In any case, this is hardly relevant to the fact that Russia faces increasing resistance from inside it's own borders, and it has no ability to realistically resist. That's going to impact Russia's staying power. Ross in the number of oligarchs falling out of windows, and it kinda looks like Putin is feeling the pressure.