Cross the River Neris in central Vilnius, turn towards the west and you pass through a pretty enclave of low wooden houses surrounded by neat gardens. Next, in the outer suburbs of the Lithuanian capital, Soviet-era blocks and their equally charmless free-market successors put their crude stamp on the cityscape. In the hilly parkland of Karoliniskes, the stone and metal needle of the television tower thrusts 325m into the sky.

Here, the Soviet Union staged its last, bloody stand. On the night of 12-13 January 1991, Soviet tanks and troops – ultimately commanded by Mikhail Gorbachev – attacked a huge crowd of protesters for independence.

Shot or crushed, 13 people died. Shamed, Gorbachev halted his aggression. An uneasy stalemate held until the three Baltic states regained their self-determination in September. The USSR fragmented. In the snow around the TV tower, Stalin’s empire had slaughtered its final victims.

Inside the broadcasting complex, a slightly scrappy memorial pays a photographic tribute to the fallen. “We still can’t tell our own stories,” said Lithuanian playwright and director Marius Ivaskevicius as he showed me round one day last autumn. Even so, this is the spot where Soviet power last inflicted large-scale casualties. Given the large Russian-speaking minorities in Latvia and Estonia, the Baltics cannot remember their recent history with one mind. But remember it they do.

In January 1991, Ivaskevicius was 17. One of his teachers, an independence activist, called on pupils to assemble on that fateful night to defend their revolution against Gorbachev’s armour. All under-18s were sent home, so he missed the confrontation. “It was dramatic, but it was our victory – our moral victory,” he said. “After that, there was no going back.”

This week, Vilnius – and Riga, and Tallinn – at last started to bleep softly on Britain’s official radar. The ripples of instability spreading from semi-occupied Ukraine have made even the gentlemen in Whitehall pay heed to what Neville Chamberlain would have called “a quarrel in a far-away country, between people of whom we know nothing”.

RAF planes escorted Russian “Bear” bombers away from the coast of Cornwall after the latest teasing probe of Nato’s frontiers. To outrage in Moscow, Defence Secretary Michael Fallon belatedly voiced his worries about Vladimir Putin’s “pressure on the Baltics”. A few breaths of Ukraine-style intimidation have already begun to waft over the region. In September, Estonian agent Eston Kohver was abducted by Russian troops from (the evidence strongly suggests) inside Estonia itself.

Back in Vilnius, we had toured the grisly cells of the KGB headquarters between 1945 and 1991, now a museum of “genocide and resistance”. In one cell, dissidents would stand in freezing water until mind or body broke. The windowless execution chamber, where more than 1,100 enemies of the USSR met their fate, is marked on the official plan as a “kitchen”. Runnels cut into the cold floor let the blood drain away. “I don’t see how you could have any nostalgia for such horrible things,” Marius Ivaskevicius reflected.

Yet simple shades of black and white will never suffice for his country’s tormented past. Between 1941 and 1945, the Gestapo took over this house of pain. They made use of keen local collaborators in their massacres of Lithuanian Jews. “First of all, we want to be victims,” said Ivaskevicius. “Nobody wants to be the killer.” He got into political hot water himself thanks to a revisionist novel about the anti-Soviet partisan leader Jonas Zemaitis. Still, not all historical memories are contested quite so grimly here. Debate rages about the Socialist Realist statues of heroic workers on the “Green Bridge” over the Neris. Should they stay or go? A gay group has even claimed them as ideals of homoerotic comradeship. Cue apoplexy among diehard communists.

From Vilnius, the world looks very different. Russia can feel much more like the “clear and present danger” Fallon sees than a pasteboard menace under a pantomime ogre. The mighty neighbour blasts TV propaganda channels into Baltic homes, and tries to exploit lingering grievances among the “ethnic Russian” population (in Lithuania, under 5 per cent; up to 40 per cent in some parts of Latvia). “It creates division, even within families,” a Lithuanian diplomat told me about Putin’s broadcast barrage. “I have a Russian mother. It means that we can’t talk about politics.”

With an angry bear in the backyard, other issues pale into near-irrelevance. On 1 January, Lithuania joined the eurozone. Does the foggy future of the single currency bother you, I asked author and TV presenter Andrius Tapinas. “Events in Russia take precedence,” he replied. “It gives us one more kind of protection.”

In this war of shadows, the Baltic states have – since they joined Nato in 2004 – sheltered under the treaty’s Article Five. An attack on one member is an attack on all. However, in the “little green men” era of camouflaged troops, cyber assaults and proxy provocations, who will know when such a violation takes place?

Anders Fogh Rasmussen, Nato’s former secretary-general, told the BBC World Service that “the single most important purpose of this Russian hybrid warfare is to try to circumvent the activation of Nato’s Article Five”. So when will the alliance admit that such a breach has happened? “We never answer that question, because it is part of our deterrence that a potential aggressor never knows how and when an activation of Article Five will be triggered.”

Come back, Dr Strangelove. But perhaps you never went away. Certainly, Peter Sellers’ crazed Cold Warrior would recognise a kindred spirit in General Valery Gerasimov. In February 2013, Russia’s chief of the general staff published an extraordinary article, “On the Value of Science in Prediction”. Surely no piece in the Military-Industrial Courier has ever attracted such worldwide attention. He updated the Russian tradition of stealth or deniable conflict – maskirovka – to lay out a detailed doctrine of war without the shooting.

As Gerasimov explained: “The open use of forces… is resorted to only at a certain stage, primarily for the achievement of final success. In the 21st century, we have seen a tendency toward blurring the lines between the states of war and peace. Wars are no longer declared and, having begun, proceed according to an unfamiliar template.” Nicely put, General – even if George Orwell got there first in Nineteen Eighty-Four.

For Gerasimov, “frontal engagements” will become “a thing of the past”. “Long-distance, contactless actions against the enemy are becoming the main means of achieving… operational goals.” Viewed from Vilnius, or indeed Kiev, the most chilling tenet of this “Gerasimov Doctrine” comes in the general’s observation that “a perfectly thriving state can, in a matter of months and even days, be transformed into an arena of fierce armed conflict, become a victim of foreign intervention, and sink into a web of chaos, humanitarian catastrophe and civil war”.

In a better world than this, no military alliance would exist – still less one that stockpiles nuclear arms. In the continent we inhabit, Lithuania and its Baltic neighbours have every right to guarantees. How, though, to enforce them in a region where “war” and “peace” now blur into some misty and treacherous no-man’s-land?

However many Bears he sends to buzz the Cornish sands, Putin is unlikely to surf ashore at Newquay with a hand-picked squadron of Spetsnaz. Neither, in all probability, will Russian tanks again crush youngsters at Vilnius’s TV tower. Rather, from Kiev to Riga, the Gerasimov games of feint, bluff and charade will intensify, boosted by a disinformation system that Marius Ivaskevicius now finds “more emotional” and extreme than in Soviet times.

This “quarrel in a far-away country” may reverberate closer to home. On the human level, about 100,000 people from Lithuania now live in the UK; Ivaskevicius has written an acclaimed play (Banished) about migrants in London. In the political arena, the Baltic nations and Poland view Nato and the European Union as twin ramparts of their liberty. This obvious link baffles our Brussels-bashing government. In pursuit of his shambolic anti-European policy, David Cameron has even managed to alienate Poland, once a key ally. That must count as a first in the annals of negative diplomacy, given that its foreign ministry was, until September 2014, run by a Cameron chum from the Bullingdon Club: Radek Sikorski.

In Vilnius, as in Warsaw, most people want to form part of what Sikorski calls “a strong, democratic European political-economic space” rather than subsisting in a buffer zone “between Western Europe and a less democratic Eurasian political-economic space dominated by Russia”. In the new age of disguised or proxy aggression, soft power rather than military hardware can best achieve that goal.