Garvan Walshe is a former National and International Security Policy adviser to the Conservative Party.

A cold ruthless calculating machine, possessed of superior insight and inured from moral scruple or political pressure. This is the image Vladimir Putin presents in the West, reinforced by mystique inherent to Russia (Churchill’s riddle wrapped in a mystery inside an enigma), buffed by KGB training and given depth by his survival of the Hobbesian St Petersburg and Moscow of the 1990s.

The conditions in which he calculates deserve more scrutiny than is usually applied in the countless pieces that claim to predict “what Putin is going to do next.”

But alhough we don’t know what he has decided (or even if he has decided), we can say something about the conditions in which the decision is being made. These are four.

First, the subject: for whose ends is he acting?

Second, time – and does he feel its pressure?

Third, options: how many does he think he has?

Fourth, instrumentality: is Ukraine an end in itself, or the means to some larger aim?

The subject features as the key in Churchill’s riddle, which the man himself indicated as the Russian national interest. The relationship between Russia’s ruler and the state has changed since Stalin’s or the Tsars’ times. Tsarist government was personal, but with an eye on the fate of the heirs to the Romanov dynasty.

Soviet authority took the long view to the extreme, leading George Kennan to quip in his famous X Article that “the theory of the inevitability of the eventual fall of capitalism has the fortunate connotation that there is no hurry about it.”

Putin is a 69 year old man in a country where average male life expectancy is 73. With no party or personal successor to think of, his interests and those of his country have begun to diverge. He built up all that political capital during his two decades in office. Is now the time to spend it?

His occupation of Crimea and thinly-proxied invasion of the Donbas in 2014 were an emergency response to Ukrainians’ ejecting Viktor Yanukovich’s kleptocracy and the Russian hegemony it guaranteed.

Its results were mixed. The seizure of Crimea itself was a masterstroke of hybrid deterrence equalled only by Cork fishermen ejecting the Russian Navy from Ireland’s exclusive economic zone.

But the war in the Donbas has backfired. It turned Russian-speaking and Russia-sympathising Ukrainians against Vladimir Putin’s state. It deprived Moscow of two regions that used to vote reliably for pro-Moscow parties. Far from being self-sustaining, the occupation has to be bolstered by an estimated 32,000 unofficially deployed Russian troops. 

The eight years of conflict have supplied hundreds of thousands of Ukrainians with combat experience, and given Ukraine time to partially rebuild armed forces that had been neglected since independence in 1991. While Ukraine still lacks important capabilities, including air defence and a navy, the balance of forces is not as one sided as it would have been in 2014.

Putin’s own military build-up has also created a paradox, by freeing the UK and Poland to supply anti-tank and anti-aircraft missiles. In addition, Ukraine has had some of its own medium-range land and sea-launched cruise missiles in service for at least a year and, next year, Kyiv is due to take delivery of new Turkish drones capable of firing long cruise missiles at ground targets. 

These new capabilities change the operational balance of any war and, if deployed at scale, would allow Ukraine to threaten Russian facilities as far away as Voronezh or Volgograd (once Stalingrad).

Though Russian forces have also undergone major modernisation since 2014, and developed medium-scale fighting experience in Syria and Libya, this could be the one of last winters before the military cost of large scale operations against Ukraine becomes uncomfortably high.

Yet it is a grave mistake to think of the decision as a binary matter of invasion or peace. A full-scale invasion that aimed to seize the country east of the Dnieper, or symbolically seize the capital is certainly within the bounds of possibility. Military police and national guard units, whose job would be to suppress insurgents and hold territory have also been spotted moving to the border. Further battalions have been sent to Belarus to directly threaten Kyiv.  Naval detachments have sailed from the Baltic into the mediterranean and will soon pass the Dardanelles into the black sea. Units from Eastern military district have been denuded of officers and professional soldiers, leaving only conscripts behind. 

This attempt to throw the kitchen sink at the Ukrainian front may itself just be cover for a more limited operation to officially seize the Donbas, and create a land bridge to Crimea.

Alexander Vindman, the American officer who denounced Trump’s attempt to trade military aid  to Ukraine for a spurious investigation into Joe Biden’s son, has a bleaker view. Russia’s aim, he suspects, would be to subject Ukraine to continuous bombardment in order to make it impossible for the state to function, without undergoing the expense of occupying territory.

Or Putin might simply increase the pace of cyberattacks, sabotage and terrorist disruption in Ukraine. The military build-up would then just be one element of a thermostat he applies to Ukrainian politics.  This may explain Ukraine’s reluctance to further damage its economy by mobilising reserves for an attack that might not in fact be coming.

Because Ukraine itself might not necessarily be Putin’s main target.  A democratic Ukraine, in a close relationship with the EU’s economy and NATO’s military support (even if not officially a member of either) with growing prosperity and increasingly capable military forces of its own of course poses a practical and ideological threat to the regional hegemony Putin is trying to restore.  But a united West poses that threat more starkly.

So in exchange for ceasing to threaten Ukraine, Russia has demanded NATO return to its pre-1990s force posture, abandoning Poland and the Baltic states, and perhaps also Romania and Bulgaria. NATO, quite rightly, has refused. Its counter-proposals, leaked to the Spanish newspaper El País, adroitly propose the restoration of mutual arms control measures that were allowed, with the Kremlin’s encouragement, to lapse under Donald Trump.  

Their formulation was a strategic defeat for Putin. His threat to Ukraine has, with the minor exception of Viktor Orbán, united rather than divided the West. What comes next depends a good deal on whether he prizes control over Ukraine over Western disunity. If he escalates in Ukraine, the West will unite against him. If he divides the West, Ukraine, he hopes, can be worn down more easily.

A military strike remains a distinct possibility, but be ready too, for Putin to surprise by doing less than expected in the hope that the more skittish members of the Alliance peel off. Understand that supposed restraint would just be a transitory stage. Ukraine needs permanent Western support as long as Putin stays in the Kremlin.