Contrary to Vietnam and Afghanistan, Russia has the ability to take large swathes of territory early, absorb it, and start moving Russians into that territory while continuously sieging major cities.

The Ukrainians will look bad if they attack the Russian citizens that are now occupying them, and the Russian army doesn’t need to convince the local population to join them but instead they can encourage them to evacuate and give them safe passage into the EU.

Eventually the country will be more and more Russian and most of the world will forget about the Ukrainians. We’re just in the initial “rough” stages where it’s the new news item and countries not actually involved in the conflict aren’t bored yet. Once they reach a stable position, they can just wait them out while occupying the majority of the country.