For many, Moscow’s renewed assault on Ukraine in 2022 marked the emergence of a new era, a tectonic shift in international affairs. The shock of the scale and intensity of the combat – the worst in Europe since 1945 – led senior officials to suggest that the world had moved from a ‘postwar era’ of stability to a ‘prewar era’ of geopolitical tension, requiring increasing defence spending and preparation for potential conflict. Some were specific: the situation was a ‘1937 moment’: while the Euro-Atlantic community and its member states are not at war, they must act rapidly to prepare and prevent one, and to do so requires a new approach.

This sense of a ‘prewar era’ has only become more urgent as senior officials and officers across the Euro-Atlantic community point to the possibility of a Russian attack on NATO within the foreseeable future. Primarily, the new approach has focused on increased defence spending. Thinking about the challenge, though, tends towards updates of the past, framing the broader picture either as a ‘return to the Cold War’ or revisiting the Nazi assault on Europe of the late 1930s, and the specific one of a Russian assault on the Baltic States. Very often, however, these are echoes and versions of debates that the Euro-Atlantic community has had for the last 20 years: a new Cold War. And all too often, the discussion about the late 1930s returns to the well-worn analogies of Munich and the Molotov-Ribbentrop pact.

In fact, 1937 offers another apt reference point for lessons about evolving strategic challenges and deterrence and defence: this was the year that then-Colonel Arthur Percival, a well-connected, decorated and upwardly mobile British officer, wrote an ‘appreciation’ of a potential attack on Singapore from the Japanese point of view. Following on-site inspections in Singapore and Malaya, Percival observed that such tremendous change had taken place concerning the whole problem of the defence of the naval base at Singapore that it could no longer be considered an impregnable fortress. Instead, the base would be in imminent danger if war broke out.

These foundations of the British plan to defend Singapore rested on decisions taken in the early 1920s. At that time, the main threat was considered to be a potential long-range, coup-de-main style strike from the sea by Japan. Since the nearest major Japanese base was 1,700km away, distance alone would both limit the scale of the attack and rob it of surprise. Once alerted to a Japanese attack, the Royal Navy would dispatch the fleet to defeat it. Consequently, the roles of the other services were largely framed towards defending the base until the fleet arrived; the coastal guns that formed the main defences faced out to sea.

To be sure, there was extended debate among the services about this plan – even in the early 1920s, some considered that a Japanese attack on Singapore would be from the north, through Malaya. And at government level, budget restrictions delayed the building of the naval base. Nevertheless, the plan that the Royal Navy should play the key part in deterring or defeating a long-range Japanese attack by sea remained the main emphasis.

By 1937, however, Percival argued that these foundations were no longer valid. First, the changing situation in Europe – Germany’s rise and the Anglo-German naval agreement – meant that the Royal Navy would be tied to home waters, undermining deterrence in the Far East. Second, Percival noted Japan’s shifting politics and military capabilities. He suggested that the main threat was no longer a long-range coup de main from the sea, but an attack on Singapore from the north: an amphibious assault to seize air and naval facilities in Thailand and Borneo, followed by a campaign down the Malayan peninsula. The jungle was not impenetrable, and an attack could be launched in monsoon season (from November to March), indeed poor weather might hinder the defence more than the attack. Therefore, he argued, the defence of north Malaya should now be the primary focus.

Endorsed by Lieutenant General William Dobbie, the General Officer Commanding, Malaya command, the appreciation was submitted to the War Office in London. Percival’s view that an attack from the north was the chief danger to Singapore was shared by others, including Chief of the Imperial General Staff, Lord Gort. But others rejected the appreciation for being too pessimistic, scaremongering and overestimating Japanese capabilities. The existing plan was reaffirmed.

When it came on 8 December 1941, the Japanese attack did not consequentially differ from what Percival – and Dobbie, among others – had argued four years earlier. Japanese forces achieved air superiority and sank the two Royal Navy capital ships in the region within two days, and, invading Malaya from Indochina and Thailand, rapidly advanced south to capture Singapore in a 70-day campaign.

There were many reasons for the fall of Singapore, from inadequate and insufficient equipment to the underestimation of the enemy, and a persistent lack of coordination between civilian and military authorities and among the services themselves. Percival himself, having been appointed commanding officer in 1941, lost the initiative at the outset and did not commit his numerically superior forces to seek a decisive battle. As he later observed, though, the failure to modify the prewar strategy in conformity with changing international conditions was the first cause of British weakness.

It is here that we find the importance of our ‘1937 moment’: it is not only spending that is important, but creative thinking about the evolving challenge and the ability to convert that thinking into policy making. Changing international geography, including alliances and partnerships, combined with socio-economic and technological development are shaping very different conditions from when NATO first began to debate whether it faced a ‘return to Cold War’ and the Russian threat in the late 2000s. At their foundation, today’s scenarios of how Russia might attack NATO too often reflect questions and answers that were originally formulated and took shape some 20 years ago despite the evolving characteristics of Russian power.

The lesson from Percival, Dobbie, and others, therefore, lies the value of what we might call ’empowered red teaming’, effective internal challenge of policy orthodoxy. Red teams can too often be drawn into the standard daily routines and procedures of policy making, and tasked with war gaming. Consequently, often they become red in name only, in practice reflecting blue. Instead, red teams in NATO and its member states can offer a much more effective contribution by being disconnected from those daily routines and being tasked with assessing how adversaries see and plan for the future. This empowerment will require both intellectual freedom and direct connection to decision-makers.

‘Our 1937 moment’ means shaping an appreciation of a potential attack on NATO from the Russian point of view and acting on it. The long-serving baseline scenario of a Russian invasion of the Baltic States appears to be the most complex and potentially costly of options open to Moscow given the terrain and NATO’s defensive preparations. So, why would it work this way, and what are Moscow’s alternatives? How do Moscow’s changing international partnerships influence this, if at all? Answers to these questions will go a long way to mitigating the perennial Euro-Atlantic sense of surprise about Moscow’s actions, and to ensuring that deterrence and defence remain not just up-to-date, but ready for the future.