Uh oh. Here we go again. Fresh off swallowing Crimea, Vladimir Putin may well be yearning not for peace but for another piece of Ukraine. At least that’s the concern raised by carefully orchestrated pro-Russian demonstrations in Donetsk and other cities in the eastern part of Ukraine where, before Russian TV cameras, the Russian minority is demanding Anschluss with the Motherland. 

John Kerry was quick to note, no doubt accurately, that these events are hardly spontaneous given the recent arrest of Russian intelligence agents in Ukraine. It is not hard to imagine a scenario unfolding whereby, once again repeating his favorite excuse for aggression–protecting Russian minority rights–Putin will send the Russian army rolling across the frontier. It would certainly not be a difficult military operation to carry out, given that the Russian forces are already mobilized ostensibly to carry out “exercises” and given the lack of military capacity in the Ukrainian army to oppose such an incursion.

What, one wonders, is standing in the way of another semi-covert invasion followed by outright annexation? The only real obstacle would seem to be any concerns Putin might have about the consequences of such aggression. Kerry, after all, has warned the Russian president he will face “further costs” for such a move. But given the fact that the costs to Russia of annexing Crimea have been minimal–and given the complete loss of American credibility post-Syria when it comes to drawing “red lines” for dictators–one must conclude that it is only Putin’s self-restraint that is preventing a further expansion of the Russian Empire. And given Putin’s track record, both at home and abroad, of grabbing as much power as possible for himself, betting on his goodwill is not a very good guarantee of Ukraine’s continued territorial integrity.