Russia & Eurasia
NATO is not going to send troops to Ukraine. We could send military assistance, but we're not going to fight the Russians.
As the Russians deplete their existing oil fields...they're looking offshore, they're looking up into the north in the Arctic area, the northern parts of Russia — and there's significant potential there. And so they want to bring fields up there online as they draw down and deplete existing fields.
The United States and Europe do not have a way to directly affect the calculations of separatists in eastern Ukraine, so the target has to be Moscow. What you want to do is press the Russians, first and foremost, to cut the supply of weapons that is going into eastern Ukraine and is sustaining this conflict, and then get Moscow to press the separatists to stop fighting.