UK begins work on dormant 'war book' as defence chief warns of Russian threat

Finland and Sweden reshape military preparedness after Russia’s 2022 Ukraine invasion

Britain is confronting the question of whether, 80 years after the last war on its own soil, the country is psychologically prepared for the possibility of war. Knighton’s warning and the government’s update of the “war book” together put that question back on the national agenda.

Knighton’s intervention came as work began on the government’s so-called “war book,” a civilian preparedness plan that has not been updated in decades. The government wants British households to stockpile canned food and drinking water, strengthen civic resilience, and prepare for severe disruption to daily life and the possibility of war. In 1940, the danger of a German invasion of the UK was very real, but the chances of Russian tanks rolling up Whitehall are surely negligible.

The historian Margaret MacMillan, author of War: How Conflict Shaped Us, said the threat most analysts now take seriously is not a conventional invasion but asymmetric operations. “It’s not the tanks you need to worry about,” MacMillan said. “It’s the cutting of cables on the ocean floor. It’s the hacking into systems on which so many things depend. The possibility for asymmetric war, for cyber war, is growing by leaps and bounds.” MacMillan argued that British society had come to treat peace as the normal state of affairs. “So no, I don’t think we are psychologically prepared… but I do think that we are beginning to recognise that war is something that is closer to us than we’d like to think,” she said.

The present moment sits within a longer historical arc. In 1914, recruitment stations were flooded with volunteers eager to serve their country, raised on heroic tales of empire-building in which war was one glorious cavalry charge leading to swift victory and everyone home by Christmas. The experience of what came to be known as the Great War seared itself into the popular consciousness and survives in collective imagination. One in eight of the men who enlisted in the UK left their bones in the fields of Flanders and France, Mesopotamia and Gallipoli. The survivors carved their unspeakable grief into the landscape with the erection of thousands of war memorials. The pain of it touched every community in the land.

MacMillan said the experience of the First World War had changed Europe’s view of conflict. “The experience of the First World War showed just how dreadful modern war is… And the idea that war could be glamorous never really came back after that,” she said.

The retired British general Sir Richard Shirreff, a former Deputy Supreme Allied Commander Europe, drew a parallel with the summer before the First World War. “In a sense it’s now a bit like those Edwardian summers before 1914, when there was a lot of talk of war but the notion of actually going to war seemed so far-fetched as to be beyond belief, and I think that’s where we are at the moment,” Shirreff said.

Andrew Michta, a Polish-born American professor of strategic studies at the Hamilton School at the University of Florida, argued that Western Europe’s leadership elites have succumbed to what he called a decades-long “crisis of disbelief.” “The Germans have totally disarmed during the last 30 years,” Michta said. “The UK is also largely disarmed and, most importantly, mentally. There is no readiness for what’s happening because the policy elites are not addressing their publics in a way that would honestly state the gravity of the situation.” When the Soviet Union collapsed in the early 1990s, many European countries began a decades-long winding down of military preparedness, dramatically cutting defence spending, in the belief that the threat from Russia had disappeared. Michta singled out Germany’s reliance on Russian energy via the Nord Stream pipelines as an example of a mistaken belief that Berlin could manage its relationship with Moscow through political and economic means. He described what he called “20 years of appeasement in Europe driven by the elites’ lack of willingness or courage… to articulate how the situation was changing and how rapidly.”

Shirreff argued that Russia’s initial invasion of Ukraine in 2014 marked the real turning point. “The reality is that Russia believes it’s been at war with Nato since 2014,” Shirreff said. “Not a conventional war, but a war designed to undermine the integrity of target states or alliances.” He said Russia could attempt to “unhinge Nato by, for example, attempting to take over Spitsbergen [in the Norwegian archipelago of Svalbard] or something else indirect.”

Mounting calls for increases in defence spending are rooted in a belief that the best way to prevent a war is to be ready — psychologically and militarily — to fight one. Not everyone agrees.

The belief that the country is under threat is key, according to the psychologist Jim Orford, professor emeritus of clinical and community psychology at the University of Birmingham. “It is what I call simplistic thinking,” Orford said. “In order to contemplate the possibility of going to war we’ve got to think in simplistic terms. In terms of enemies and heroes. We’ve got to think of Russia as an enemy. The narratives are all simplified.” Orford described three stages: “Being [psychologically] prepared for war is the first stage. Contemplating war is the second phase and then actually engaging in war is the third. I think we’re well into the ‘contemplating war’ phase.”

This “crisis of disbelief,” as Michta put it, is not evenly spread. The further east you go, the closer you get to the Russian border, the more alert a nation’s people are to the threat, and the more psychologically prepared.

East of the United Kingdom, the debate has moved further and faster. Sweden, which had not fought a war in two centuries and had pursued a policy of neutrality for centuries, abandoned that policy after Russia’s full-scale invasion of Ukraine in 2022. Swedish Prime Minister Ulf Christersson told The Economist last month: “Russia is self-evidently dangerous.” He added: “We don’t know when it [the war in Ukraine] ends, but how it ends will define the security situation in our part of the world for at least a generation.” Asked whether Russia should be seen as a potential aggressor even after the war in Ukraine is over, Christersson said: “Yes. We have a few hundred years experience of this… We know Russia pretty well.”

Sweden now operates a system of partial conscription in which all school leavers must register for military service. The armed forces select and conscript the strongest candidates, who then complete up to 15 months of training before returning to civilian life or higher education. Conscripts then become part of the country’s large reserve force. Minna Alander, an analyst at the Stockholm Centre for Eastern European Studies, said the change had become a social expectation. “It was almost an internet joke in 2022 and 2023 that everybody wished for a call up,” Alander said. “Sometimes people get frustrated if they haven’t been called up for a long time. It’s an expectation for sure.” Sweden has also begun identifying civil engineers with relevant skills who could be exercised in case of disruption. “Sweden has, for example, been identifying civil engineers with some relevant skills in, say, electricity supply who could be exercised in case of disruption. So Sweden can access this pool of civil engineers [who know] what they could do and how they could be activated,” Alander said.

The three Baltic republics — Lithuania, Estonia and Latvia — also know Russia “pretty well,” having regained their independence from Moscow only in the 1990s. German troops, who invaded Lithuania in the 1940s, are now back on Lithuanian soil, this time by invitation, to bolster that country’s defences against the threat from the east. A thousand British troops lead a multinational force in Estonia for the same reason.

Finland is the country most often cited in European debates as a model of mass civic preparedness. Of the roughly 100,000 Nordic citizens who died in the Second World War, 90 percent were from Finland, killed in the Winter War of 1939–40 against the Soviet Union. Today Finland shares an 800-mile (1,287km) border with Russia. After the full-scale invasion of Ukraine in 2022, Finland quickly abandoned its historic neutrality and joined NATO alongside its neighbour Sweden.

Finland operates universal male conscription, with some women also volunteering to serve. On completion of service, conscripts become part of Finland’s reserve force, which has the effect of closing the gap between the professional military and the civilian population. The retired three-star general Arto Raty, a former permanent secretary of Finland’s Ministry of Defence, said the system binds society into national security thinking. “If conscription is done well, it ties every single family into national security thinking. Your grandfather, your great-grandfather and your sons, they all go to the same military service,” Raty said. “We bind the whole of society into supporting the military. Every single hospital has its crisis tasking. Every water supply agency. And interestingly, the most publicly trusted organisations in Finland today are the military, the defence forces and the police. That is not the case in most countries.”

Finland’s military also runs a series of courses annually for leaders of society — members of parliament, government ministers, chief executives of private enterprises and public utilities, the health service, NGOs and churches. “We train them in crisis management, so that they understand how society will work in a crisis. We’ve been doing it every year since 1960,” Raty said.

With a population of 5.5 million, Finland has a professional defence force of 23,000 — compared with the UK’s 70,000 from a population of 66 million. Finland also has a trained reserve force of close to one million and can mobilise a reserve army of 280,000 at short notice. In 2025, Finland spent 2.5 percent of its GDP on defence, comparable to the 2.3 percent spent by the UK the same year.

Should the rest of Europe go to the expense of following Finland’s lead when the prospects of a conventional war with Russia seem vanishingly remote?

Shirreff argued that the British army of 70,000 would be inadequate for the kind of war the country would have to face, and that some form of national service was necessary. “An army of 70,000 is simply not going to cut the mustard in the sort of war we are going to have to face,” Shirreff said. “So I don’t see how we could generate the military capability needed without some form of call-up.” He pointed to the Norwegian model, in which every school leaver registers for conscription, completes a year’s training, and then returns to civilian life with national service on their CV. “There, every school leaver is registered for conscription… and they go and do a year’s training after which they go on to university and when, later, they are competing for jobs, if they’ve got national service on their CV, they’re seen as the best candidates… That’s the sort of thing we should look at,” Shirreff said. He added: “The case has to be made honestly by political leaders who must really look the population in the eye and say ‘this has got to be done for us to be secure’.”