I'm not sure what the answer is, I am just not comfortable at present with the assumption that a glass of milk and a hug is what the Russian population should receive for starting a criminal enterprise, irrespective of how it turns out.
How about looking at the problem from a completely different perspective: What's the most cost-effective way to defend against Russian aggression over (say) the next 75 years?
I don't know the answer to this, but we have some historical examples of the different approaches. Germany and Japan both required significant investment in reconstruction, but no-one has to spend money defending against them any more. Investment in North Korean reconstruction was minimal, but it remains a threat that costs money to mitigate.
The bottom line is that prosperous countries generally don't wage wars of aggression because they have too much to lose.
We obviously can't reconstruct Russia in the way we did with Germany and Japan without invading - which no sane person is contemplating - but building a wall around them and leaving them to suffer isn't likely to work either.