IT’S almost exactly seven years ago now since I first arrived in the city of Donetsk in eastern Ukraine’s Donbas region.

Back then just off Pushkin Boulevard in the heart of the city, pro-Russian separatists occupying the city hall had already hoisted Soviet-era banners and every day the barricades grew higher and more heavily manned.

For weeks during that April of 2014, the separatists had been storming and occupying government buildings and seizing weapons. Tense as things were back then, this was only the beginning.

Few at that time could have foreseen what was to follow, as the city became the hub of what would be known as the Donetsk People's Republic (DPR), sustained by Russian military and materiel support. This was a story in itself that was to bring myself and other correspondents back time and again.

Today those same pro-Moscow separatists that I met on the Donetsk barricades all those years ago are now dug in along the frontline of an all-out war with the Ukrainian government in Kiev.

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It’s a war that rarely makes the news headlines though it’s estimated to have killed 14,000 people. A war too that fluctuates in intensity but has never gone away despite a 2015 peace agreement called the Minsk accords.

For many politicians and diplomats, it’s a war they prefer also to call a “crisis” or “stand-off" as if by using the word “war” they might inflame the situation.

But every so often the threat of escalation rears up and those same political leaders are forced to face the harsh reality of a potential all-out conflict that would have massive geopolitical implications. Right now, is just such a moment.

It comes in the wake of Russian President Vladimir Putin ordering the massive build-up of troops on the Ukrainian border, the deployment of four warships from the Russian Baltic Sea fleet to reinforce units in the Black Sea and a significant spike in separatist attacks on Ukrainian forces.

On Monday NATO also reported an “unusual peak” in Russian flights near the fringes of the alliance, and a rise in the need for interception of Russian aircraft. Put quite simply, NATO is nervous despite Kremlin assurances that these are only exercises.

So nervous in fact that the United States, UK, the European Union and NATO countries have all openly expressed their “unwavering support” for Ukraine and called for a meeting of the alliance’s North Atlantic Council.

But while Moscow and Kiev blame each other for a rise in violence, tensions continue to grow raising the all-important question, why now?

“Maybe these are exercises, maybe more,” was how one senior US official described the situation to the Washington Post, in what some observers are interpreting as being a test of US President Joe Biden’s administration by his Kremlin counterpart Mr Putin.

One EU diplomat was more explicit in his concern, telling the online paper EUobserver, “I'm worried something bad’s about to happen... a Russian provocation, followed by Russian accusations of Ukrainian aggression: the Georgia scenario,” the diplomat said, referring to the Georgia war in 2008, when Russian tanks nearly overran Tbilisi.

To some extent we have of course been here before in eastern Ukraine as ever since the signing of the Minsk-II accords several war scares have erupted but fizzled back to the low-intensity conflict of attrition that has been ongoing in the region.

But this time insist some security analysts, things are different. To begin with they point to how Russia is losing the political initiative.

For Moscow, Minsk II has become an increasingly frustrating obstacle to achieving its objective of extending its influence over Ukraine through a combination of hard diplomacy and soft coercion until 2014 and by hybrid war ever since.

At the same time Russia has grown in military strength and any such external ‘gains’ only help bolster Mr Putin’s position at home even if the Russian economy is not especially healthy.

As James Sherr, Senior Fellow at the International Centre for Defence and Security (ICDS) summed it up, “the combination of political necessity and military opportunity is never auspicious.”

In short three possible scenario present themselves over the stand-off. The first is that Mr Putin might simply be putting the squeeze on Europe and Ukraine for further concessions. He could for example be looking to pressure Kiev into giving the Russian separatist authorities in occupied east-Ukraine “special status” with constitutional powers.

Mr Putin’s best way to do this would be for Russia to up the ante with the West over Ukraine who in turn might lean on the country’s president Volodymyr Zelensky insisting that such concessions would be better than any all-out war. The second scenario and linked to this as previously mentioned, is that Mr Putin is stress testing the Biden administration.

The third and nightmare scenario is of course what Ukraine's EU ambassador, Mykola Tochytskyi, called “Putin’s dream” of “reconquering Ukraine with a view to restoring the Russian empire.”

As the well-known Russian military analyst Pavel Felgenhauer has pointed out, to fully understand this from the Kremlin’s perspective it’s important for those of us in the West to put ourselves in the mindset of the Russian military establishment.

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In short says Felgenhauer it perceives the West itself as “waging hybrid war against Russia on many fronts: in Belarus, in Ukraine, with respect to Alexei Navalny. And Russia must not sit defensively, but actively counter-attack.”

This third scenario, one of actual Russian invasion of Ukraine though unlikely cannot be ruled out say some observers.

“The thing about Vladimir Putin is that when we are thinking about what he is going to do, we are trying to think that it’s going to be something rational,” was how Kirill Mikhailov, a researcher with the Conflict Intelligence Team, which tracks Russian military involvement in Ukraine summed up such a scenario to Foreign Policy magazine this week.

If an ‘invasion’ of sorts does come about, the likelihood is that it would probably be of a dramatic, localised type in the region allowing what Moscow might dub as Russian "peacekeepers,” being deployed. This would give Moscow an extension of its influence on the ground but stop short of going further. But even this would present a highly dangerous development and crisis.

The biggest danger of all in this test of wills of course is that either side miscalculate its actions. Should that happen this all but ‘forgotten’ and bitter war would certainly find itself in the headlines much to the world’s alarm.

Our columns are a platform for writers to express their opinions. They do not necessarily represent the views of The Herald

David Pratt is Contributing Foreign Editor