So what? In China, they think they are the rightful hegemonic power to liberate Native Americans in the US and avenge their great ancestors.
What Russians think and are taught is irrelevant to anybody but Russians and is certainly no formulated argument in itself, to give them a right to any lands.
Show me decades of academic texts elaborating this alleged widespread belief, and I will become suddenly unable to expose idiots who spout that doctrine as widely held to be fools.
What Russians think is key to anticipating what they will do.
Anyone regardless of position attempting to prognosticate Russian actions either political or military while simultaneously ignoring what they think is a fool at best.