With what?
Russia has been wringing itself out to find enough soldiers to continue the war in Ukraine, and while they haven't been driven out just yet, I think it would be somewhere between "a massive stretch" and "flat-out untrue" to say they're winning.
And by and large, the rest of Europe is farther away, has a much worse/less clear casus belli from Russia's point of view, and, crucially, is part of NATO, and thus will not be fighting alone (and yes, I know Ukraine is getting a lot of support from Europe, but support isn't the same as boots on the ground).
If Russia launches an offensive against the EU, there's a damn good chance that offensive boomerangs right back around into its face.
The war in Ukraine is currently in stalemate and for Russia the most deadly war since WW2, but Russia until now didn't execute full mobilization and full scale war. The cost of full scale war would be terrible, deaths in WW2 were counted in millions (for both soldiers and civilians). Russia didn't launch an offensive against the Europe (especially Baltic states and Poland), because they are still under US nuclear umbrella.
Oh, I don't, believe me! But the thing is, Putin is already doing this.
AIUI, he has been conscripting soldiers to fight in Ukraine for quite some time—to the point that he's had a hard time finding more conscripts already. I don't think there's much more he can do to force Russians onto the battlefield for him, wherever that battlefield is.
So there are real constraints on what Putin is able (or at least willing) to do.
Also, AIUI (and I could well be wrong), he at least says that he's not sending the conscripts to actually fight in Ukraine. Whether that's actually true... I have no data.
In 21st century warfare, what exactly is considered a 'dirty', and what is considered an 'honorable' tactic? Is there an objective definition?
...at least if you believe EU/UA propaganda.
It's funny how they yesterday or day before yesterday annouced 21st round of Russian sanctions.
"The definition of insanity is doing the same thing over and over and expecting different results."
Imagine you are so dumb, you do it 21 times and expect voters will take yous eriously and keep supporting if they paid it 21 times from their own wallets.