Maybe that's what Putin had in mind when, in July 2021, he published his (now controversially famous) historical research piece On the Historical Unity of Russians and Ukrainians. ;=) Insofar as he must be execrated for his aggression, hardly anybody could now argue that these Siamese twins of a nation are much suited to lose-lose fight without end. Now ask yourself, who'll come and bring the spoils of war when they, and the EU, finally enfeeble themselves to the point of no return? Citing Kierkegaard, precipitate repentance is false and is never to be sought after.

Additionally I urge you to read morosely prophetic Eclipse trilogy (aka A Song Called Youth) by John Shirley, where (in first edition, at least) WWIII starts in early 2020s with the annexation of Ukraine and Belorussia by Russian neosoviet regime. However, motives of the invasion as stated by Shirley are very dubious, bordering absurd: Russia, according to him, embarks the (non-nuclear) conquest of Europe out of necessity of... finding new arable lands and food producing regions. Barring this relatively minor detail, Eclipse is wonderful, a forgotten gem of cyberpunk fiction. Other two novels are produced from a weaker mix, though.

My article about one of them is here (in Russian, though you might find useful to study it just for that reason).