Those same Fascists probably won't attack Russia though, as it would be very dangerous and difficult, they're more likely to blame NATO for "stabbing them in the back" and target them instead, since they're less likely to be stopped in act and less likely to actually face any consequences themselves. Fascists are cowards.

And this benefits (the leadership of) NATO countries as well, a terrorist threat (that they can just blame on Russia) gives them an excuse to increase military spending and do more austerity measures, they don't really care if a train station gets bombed every now and then, it just gives them an excuse to reduce funding for the railways.

That's how I see it playing out at least, I could be wrong though. And they would certainly try to engage in terrorist attacks in Russia and the newly occupied territories in Ukraine, but again, I imagine Russia would be aware of this and crack down hard on any potential terrorist activity.