|Time to decide what you're going to do|
The question of what Putin's motivations are in Ukraine has been uppermost. It seems irrational to give up so much, to accept so much geopolitical and economic risk for so little gain. There was a kind of historical logic to the annexation of Crimea, but the continued escalation in Eastern Ukraine appears to be events spinning out of control
But maybe that's the wrong way to think about it. The whole Ukraine story-arc began with the Maidan protests, when their Russian puppet government rejected a perfectly benign trade agreement with the EU and attempted to commit the nation to the Russian orbit. The people rebelled, the Yanukovych government collapsed and the die was cast. So if you're Vladimir Putin, what you want to prevent is Eastern and Central European nations, your 'near abroad', from pursuing closer relations with the West, particularly with the NATO alliance. And the most effective tool he has to accomplish that goal is fear. And in order to establish that kind of geopolitical intimidation, he has to make certain that leaders in all the Capitals of Europe understand that NATO and the West will not act militarily to check Russian aggression.
When you think about it from this strategic direction, the aggression in Eastern Ukraine isn't about accruing territory or access, or even about convincing Kiev that a cozy relationship with Brussels or Washington comes with risks. It's about demonstrating that Russian aggression will go unchallenged in Eastern and Central Europe. If those nations cease to believe in the NATO umbrella, if they realize that the West won't fight and the Russians will, then they will behave accordingly, and the risk that they will spin further out of Moscow's orbit will be foreclosed.
As a thought experiment (although it's being openly discussed in Europe), suppose Russia deployed a small (sub 100kt) nuclear weapon against a town in Eastern Poland or Romania. Just one bomb, complete silence, business as usual other than that, no elevated strategic force readiness, no threatening posture to the US or Europe. Would the US or NATO launch a retaliatory nuclear strike against Russia? That would guarantee a larger nuclear war. To do nothing would limit the damage to that single town in Poland. The more time that went by without retaliation, the less likely retalliation would become. Sure, there would be hysterical global outrage, there would be massive economic sanctions, but the Kremlin would have proven once and for all that they were not constrained by NATO's presence, indeed, that NATO was all talk and the smart political play would be to stay tightly aligned with Moscow.
It's hard to be certain of anything - Putin could decide to cut his losses and back down at any moment. But I'm becoming increasingly convinced that the goal is to establish at a visceral level the NATO nations utter unwillingness to commit to all-out war against a powerful adversary like Russia. At the end of the day, that might be a good thing - nations deciding that in the nuclear weapons era major-power conflicts might not be worth engaging in.