Thinking that this is just between Russia and Ukraine is such a common mistake. Ukraine is the latest move in a larger chess game (remember Transnistria, Georgia, Bellarus?) where the end goal of Russian is a new world order. Instead of the current order based on western values and laws, Russia wants the so called "uni-polar world" to change such that it has it's own sphere of influence. That sphere would consist of weak countries subjected either politically, economically or militarily. It sees those as buffer states... and there are never enough of those.