John Kerry, Secretary of State, USA states that it would be a serious breach of a UN agreement if the brought forward referendum was to be held whilst Russian troops occupy Crimea.
If disguised armed troops were to suddenly police your home town, and you know your history it does seem a little heavy handed Mr Putin, and the rest of the world thought it was very amusing of you flexing Russian forces to teach Ukraine the cost of independence is that they are in fact completely under the control of Russia anyway especially where strategic interests are concerned that pose a threat to both Russia and Ukraine.
It is not a merely the moral question of “How can Putin be right? He is invading a sovereign country protected by treaty!”
It is a military question of “How can Putin lose control of a Naval presence in the Black Sea?” and it seems most logical to assume that lacking a client government in Ukraine he would feel a need to protect it’s naval assets. You can hardly deny Russia’s obvious existential imperative may be the driver here rather than purely empire building, the later would be unconstructive. Russia would benefit far more letting European values in rather than keeping Europe separate as the 21st century progresses.
A solution is to allow Crimea to have quasi independence. And to have mutual defence agreements from both its large neighbours. It would then control huge gas and/or mineral resources. I think Russia sees that as a reason to never allow this impractical utopian ideal.
Therefore it is almost certain that John Kerry will get to restart the Cold War, Monday. I think Putin will hold some kind of moral advantage if the Referendum is 80% Russian leaning, then it is back to the USSR.
Russia Making a land grab for Easter Ukraine has an economic rather than military logic. And that is what would display a less logical and more despotic intend by Mr Putin. If Russia were to protect its military assets in Crimea, the West is going to be hard pressed to make sanctions stick, but to divide Ukraine which appears to be its next logical war strategy, I think will seal Putin’s fate. I think even China will isolate Russia (despite its own comparable occupations and tremendous land grabs).