Sure because Russia has a long history of attacking Western Europe unprovoked. Napoleon, WW1, UK US intervention in the Revolution, Polish Invasion and WW2 clearly had Russia as an Aggressor.
In all fairness OP was mentioning Western Europe. One could argue about the validity of ideologically partitioning Europe into an Eastern and Western part (I know I'm also guilty of that) but that's another discussion.
I'd say that was done fairly organically given the split between ethnicities and Orthodox vs. Catholic churches. Ukraine seems to straddle one of those boundaries.
I think you don't know your Russian history. That territory has usually been controlled by an aggressive, expansionist regime. How did you think it got to be the largest country on earth?
It's very strongly related to the geography of the region.