I think of the big lessons learned over the decades is that “wanting to win” is one of the really crucial aspects.
If Russia goes in, they will “want to win”.
Ukraine will defend, and they will also “want to win” but may have a tough time against Russia.
Does Belgium “want to win”?
Does the US “want to win”?
Does Germany “want to win”?
I say “No”.
I don’t think “capability” is a prime determining factor. It’s the desire that matters. And Europe doesn’t really want a war. So this is likely to be quick.
Germany said they want NO PART of this.