Sorry but, what? Putin has been happy to commit war crimes including genocide, torture, mass killings, and abduction of children. Putin has no need or wish to justify anything. He can just go on Russian TV and say whatever he wants and no one in Russia is going to question it.
Russians are not westerners. Even if most Russians superficially look like westerners, They do not think and they do not act like westerners. Stop ascribing westerner logic and motivations to their actions.