The Ukrainian soldiers watch and wait, nervously peering through a periscope from an icy trench at a forward observation post in eastern Ukraine.

Western governments have sounded alarms that Russia is prepared to attack Ukraine at any time. The Biden administration is considering moving troops, warships and artillery into eastern Europe and Nato announced on Monday that member countries are sending ships and jets to the region.

But how, exactly, military action might start has become an anxious guessing game for military analysts, for western and Ukrainian officials — and not least for Ukrainian soldiers, who are likely to be the first to find out.

“I would rather have peace,” said Ihor, a sergeant who is the Ukrainian unit’s cook and offered only his first name and rank. “I have two kids at home.”

If an incursion does come, most military analysts agree it won’t begin with a massive show of force — tanks rolling over the border or a sudden and devastating strike from the air. Rather, it would start with a more ambiguous, limited action that Moscow would use as justification for a wider intervention.

Such an action, American and Ukrainian officials say, could come in many different forms — the seizure by Russian-backed separatists of a disputed piece of infrastructure, like an electrical plant, for instance.

Ukraine estimates that Russia has about 127,000 troops near its borders. The build-up, said Dmitry Adamsky, an expert on Russian security policy at Reichman University in Israel, “is visible enough to let people imagine a range of scenarios that might happen. At the same time, it’s uncertain enough to conceal the strategic intention”.

Russia has repeatedly denied in recent weeks that it has plans to invade Ukraine and said it is Russia whose security is threatened.

Analysts say Russia has a rich repertoire of tricks that make it all but impossible to guess a first move. It demonstrated that with its first incursion into Ukraine in 2014. At the time, masked, mysterious soldiers appeared in Crimea in a military intervention that Russia initially denied but later acknowledged.

(New York Times News Service)