Six weeks ago, the war in Ukraine was at a stalemate, in which neither side could win but neither side could lose. Substantial Russian gains would be countered by more NATO help for Ukraine, but major Ukrainian advances could lead to Putin threatening extreme escalation.
That combination of violence with stalemate seemed likely to last through the winter, with scores of soldiers and civilians killed every day and destruction meted out to towns and cities across Ukraine. Since early December, though, much has changed, bringing the prospect that the war could alter drastically in a matter of weeks.
Precisely how that might happen is impossible to predict, but there are several elements to factor in.
