The greatest tank battle ever fought was fought in late summer 1943 about 50 miles from the Ukraine Russian border in Kursk, Russia. In that epic battle, the Germans were in German tanks and the Russians were in Russian tanks. In any fight between Russia and the Ukraine, the combatants will be shooting at tanks that look a lot like their own tanks. Both the Russians and Ukrainians have developed tanks that they do not share, but the chassis are generally all a variant of some form of a Russian tank. In the dark and smoke covered battle field you would have to question whether current infrared optics will be able to consistently distinguish friend from foe.
What ever the final outcome, if the Ukrainian army puts up a fight, there will be a lot of Russian soldiers killed, ironically by one of the only armies on earth where the soldiers all speak Russian. Putin may have some long term imperialistic goal of world conquest, but on historical terms, it is difficult to imagine he will be considered anything but militaristic aggressor and another name on the long and growing list of Russian leaders blamed for Russia’s misery.