Having failed on several occasions to calm tensions in Ukraine, Russia and the West are being pushed by a deteriorating situation into a rapidly narrowing set of options. In coming days, the outlook will seem particularly complex, and the outcome could be bad for all involved.
Viewed from Western capitals, no combination of carrot or stick seems capable -- at least so far -- of deterring Russia and President Vladimir Putin from interfering in Ukraine. The annexation of Crimea has been followed by spreading instability in eastern Ukraine that the West insists is driven, at least in part, by Russia.
