Actually, Putin does believe it. He's stated many times, as have his subordinates, that his goal is the absorption of "Little Russia" and the rebirth of the Rus

Actually, Putin does believe it. He's stated many times, as have his subordinates, that his goal is the absorption of "Little Russia" and the rebirth of the Russian empire to stand at her rightful place as a primary power in the world (and as payback for the many humiliations she has suffered at the hands of the West). You can see it in how quickly Russia installs collaborators in Ukrainian regions who suddenly declare that they wish to be annexed by Russia. These kinds of idealistic psychopathic people do exist, and they are incredibly dangerous if they get into positions of power.