I don't agree with your understanding of the recent events. The first question that comes to mind is, does the Russian army want to fight a US style war? Occupy the target country under a fake excuse against the will of its inhabitants? The answer is NO, neither Russian economy can withstand such a scenario.
Russia wants its people stop suffering from western racial segregation. To reach this goal, they have to occupy Russian living parts of Moldova too.
In fact Russians are not going to occupy parts of EU, they want Russian lands return to their country. And so far they have used Soviets era military hardware against Ukraine for 2 reasons, first and foremost Ukraine is not a match to to RUssian military power, and secondly they save money by dropping outdated missiles on Ukrainian positions.
The fact that US led Euro-vassals hate RUssian speaking people, convinced Russia to defend its people from western led racism hence war on Ukrainian NAZIs.