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.

One is public opinion within Russia. Anti-war feeling has increased since the start of partial mobilisation last autumn, and it stems from more than one base. One is older Russian men with military experience who are deeply critical of the conduct of the war and of what they see as the incompetence of the senior military, even extending that criticism to Putin and those immediately around him.

Another important base, though, is drawn from a much larger group of Russians who are sick of the strictures brought by the war, a feeling often exacerbated by knowledge of the large number of young Russian soldiers who have been killed or maimed.

There is one caveat here, though: the shift in public opinion does not amount to a clear-cut anti-war movement. This is at least partly due to media control and the ready suppression of dissent, but there is another factor at play.

Many Russians may be dismayed and depressed that the war continues, but this does not mean that they want Russia to lose and be humiliated on the world stage. If Russia was forced out of Ukraine, the fear is that it would be prey to even more NATO expansion, possibly threatening the integrity of the state itself.

That sentiment fits in with Putin’s own claims, expressed early in the war, that Russia had to win in Ukraine to pre-empt a pattern of NATO expansionism that had been ongoing ever since the break-up of the Soviet Union over 30 years ago.

Another factor to take into account is the lack of progress on the battlefield in Ukraine. In light of this, the Russian army has fallen back on maintaining control of parts of Donbas, with an emphasis on trying to occupy the salt-mining town of Soledar as a prelude to the more strategically significant city of Bakhmut. Its occupation would be largely symbolic – as the first significant Russian gain for some months – but despite Kremlin claims, what is left of Soledar is still contested.

Putin has also replaced General Sergei Surovikin as head of the military in Ukraine. He now comes under General Valery Gerasimov, the current chief of general staff. Given that Surovikin was seen as a tough and uncompromising general, his demotion within three months of appointment does look close to desperation.

Yet another problem for Putin is that his economic war is not going well. Anticipating a harsh winter in western Europe, the Kremlin was hoping for power cuts and inflationary gas prices, which would help to build public opposition to the war in the EU and NATO countries. That has not yet happened as global energy prices have peaked and the weather, so far, has been quite mild. Support for Ukraine in most NATO states remains high.

The Ukrainian armed forces have taken considerable losses in the past 11 months, yet Kyiv sees itself in a strong position. It would be even stronger if more modern weapons were available, and there have already been some key developments here, including the provision of a range of versatile light armoured vehicles from Germany, France and the United States that can move troops around rapidly.

Given its progress since the start of the war, Ukraine’s official position is to support its end only if Russia is the clear loser. This may be the official position, but what Ukraine actually does is far more dependent on the US than anyone in Kyiv or Washington is prepared to admit.

At least since the end of July, the overall pace of the war has been dictated by Washington. Ukraine has been able to resist the Russian occupation and even push back. But its success has always been subject to the weapons, training, intelligence sharing and other support from the US. The provision of the HIMARS weapon system back in August, for example, made a major difference, but if the US had also provided the much longer-range ATACMS Ukraine could have gone much further in pushing the Russian forces back towards the border.

Now, however, US policy on the war may be changing, an indication being the decision to provide Ukraine with the Patriot advanced anti-aircraft and anti-missile system. Ukraine army personnel are being taken to the US for a concentrated six-month training programme with the Patriot so they can fully utilise its potential. Other advanced systems may follow.

It seems possible that the view from Washington now is that any threat of escalation by Putin would be a bluff. Russia’s status has been so diminished by the failures of recent months that even a nuclear threat would be widely condemned by many countries, including supporters of Russia, especially in the Global South. The threat itself would be an admission of abject failure, damaging Russia’s position in the world so much that it would be better to sue for peace, starting with a ceasefire which would be widely welcomed.

The problem is that this may be wrong and a serious misreading of Putin’s world view. After all, western states do not have a good track record of predicting the course of major conflicts – witness Afghanistan, Iraq and Libya. The more that wise minds can argue the case for a negotiated end to the war short of full victory for either side the better.