What do the following pairs of arch enemies have in common: Mary Queen of Scots and Queen Elizabeth I, Churchill and Hitler, and Napoleon and the Duke of Wellington? The answer is that these great historical duos never met. Yet these bitter rivalries ended up in each case with the death of one and the glory of the other. It is tempting to ask the unanswerable: would the outcome have been different if they had known each other personally? All three had been corresponding in different ways, parlaying through intermediaries or in open violence; it is not at all clear whether the intricacies and intimacy of written correspondence, or the filtered analysis of the broker, increase or reduce the chances of better understanding.

The non-meeting of these three pairs is too tempting for film-makers and counterfactualists. Ridley Scott had his Napoleon (Joaquin Phoenix) meet Wellington (Rupert Everett) on board HMS Bellerophon in July 1815. In a 2018 biopic, Mary Queen of Scots (Soairse Ronan) meets Elizabeth (Margot Robbie) in a sunlit barn with curious gauzy drapes. A 1981 TV series, ‘Winston Churchill: The Wilderness Years’, has Hitler (Günter Meisner) sitting in the same Munich hotel restaurant staring at Churchill (Robert Hardy) sourly. In real life Churchill had – through a German acquaintance of his son Randolph – invited Hitler to dinner in the Hotel Continental in late August 1932, but Hitler stood him up.

Thus, in contrast to a panoply of well-heeled Brits, Churchill avoided Hitler, but not on purpose. He was later to suggest that such was Hitler’s charm that it was better not to have met. This raises a question for our modern political leaders: how much confidence must one have in one’s own persuasive capabilities to believe that a meeting with a political opponent can be turned to advantage? Should you trust your instincts if you feel that a meeting has gone well or appear to have won concessions? The obvious contrast with Chamberlain, who hoped for reasonableness, for one last discussion to avert catastrophe, is easy to make with hindsight.

Churchill’s initiative in August 1942, to travel to Moscow to meet Stalin (‘the ogre in his den’) illustrates the role of physical presence and emotion in the conduct of diplomacy, as well as the difficulty they present to officials. It also shows the potential value of personal connections in the state-level competition for friends. Like many a political leader, Churchill was caught between his personal and political aversion to – in this case – communism, and the manifold other balancing factors for Britain. He was vehemently anti-Bolshevist, anti-Communist, anti-Soviet. He had supported the White Russians in 1919 and saw the Bolshevists as ‘avowed enemies’ and in 1931 the USSR as the ‘gigantic menace to the peace of Europe’.

In his first year as prime minister, Churchill had sent two messages to Stalin, via Sir Stafford Cripps, the British ambassador from 1940-42, but did not receive a reply. Cripps – a British Labour politician and communist sympathiser – had disappointed by failing to develop a good relationship with Stalin. In particular, Cripps had not been able to convince Stalin to believe the British warning, passed on 3 April 1941, that the German military were preparing to invade the Soviet Union. Churchill felt Cripps had bungled this communication, but drew the conclusion that there was little to be had from trying to curry favour, commenting to Foreign Secretary Anthony Eden that it was better not to run after the Soviets with ‘frantic efforts to assure them of your love’.

When Operation Barbarossa began on 22 June 1941, Stalin flipped from villain to necessary ally. Churchill and his government had an opportunity but also a dilemma: how to help the Soviet Union win without ending up with an even bigger problem if they pushed westwards into Europe and overran Germany before Britain could. At this point communication with Stalin was in written form by telegram. By the autumn he had made a series of demands for British assistance – from soldiers and weaponry, to a declaration of war on Finland, Hungary and Romania, to the opening up of a second front in western Europe. The most senior British official to visit Moscow at this time was Lord Beaverbrook, then minister of supply.

After Hitler’s declaration of war on the US on the morning of 11 December 1941, four days after the attack on Pearl Harbor, Churchill found himself in a constantly shifting equilateral, isosceles and scalene triangle with Stalin and Roosevelt. The question was which country – the Soviet Union or the United States – would have the greatest influence in the eventual shape of a postwar Europe, and how best to position Britain to maximum advantage.

While figures responsible for making policy towards the Soviet Union (Foreign Secretary Sir Anthony Eden, his Permanent Under-Secretary Sir Alexander Cadogan, Lord Beaverbrook, and the Chief of the Imperial General Staff, General Alan Brooke) debated options for varying degrees of concession to Soviet demands, the likelihood of Soviet treachery and American unreliability (not least because Roosevelt – though only through letters – had a better relationship with Stalin and had suggested to Churchill that he would take the lead), another option emerged in the minds of Churchill and his new Ambassador to Moscow, Sir Archibald Clark Kerr, an unconventional Australian-born Scot.

Clark Kerr was convinced that the fact the two men had never met would be to Britain’s disadvantage. But there were serious risks: Churchill could not give Stalin what he really wanted, namely the opening of a second front in Europe. Stalin had written to Churchill in no uncertain terms on 23 July: ‘I must state in the most emphatic manner that the Soviet Government cannot acquiesce in the postponement of a second front in Europe until 1943.’

What was the point in going to see him if only to disappoint him? Clark Kerr felt that if Stalin could meet Churchill personally, feel the force of his personality and the emotional fighting spirit, that the two warlords would become comrades-in-arms, able to work through differences of military timetabling. For Churchill this visit had the added advantage of beating Roosevelt to a personal meeting. He needed not only to defuse and deflect Stalin’s demands, but also to win him over to his own plans for winning the war, which were not the same as the Americans’, recently arrived and with their own ideas for Europe.

The choreography of bringing these two notorious tempers together and keeping them together is detailed brilliantly in a vignette by Martin H. Folly. Churchill took only a skeleton team with him – of the senior policy figures just Cadogan from the Foreign Office and Generals Brooke and Wavell from the Ministry of Defence – and, as a last minute addition, the American Averell Harriman, who was Roosevelt’s personal envoy in London. The Soviet ambassador to the UK, Ivan Maisky, was reporting to Stalin on Churchill’s intentions and motives, astutely noting that Churchill sought to position himself as a link between the United States and the Soviet Union.

Churchill stayed in Stalin’s dacha, not the British Embassy. The first meeting with Stalin took place on 12 August 1942, and in Churchill’s opinion it went rather well. Clark Kerr’s private papers vividly describe it:

It was interesting to watch the impact of the two men clash and recoil and clash again, and then a slow but unmistakeable coming together as each got the measure of the other, and in the end, much apparent understanding and goodwill. (…) At times both were very blunt, as if each one sought by his bluntness to make a dint upon the other. I think that each succeeded and that the dints were deep. Each one was very restless. Stalin kept getting up and walking across the big room to a writing table into which he delved for cigarettes. These he tore to bits and stuffed into his absurd curly pipe. In his turn the P.M., when he had shot a bolt, got up and had a walk, pulling from his heated buttocks the seat of his trousers which had clearly stuck to them… There was something about this dumpy figure plucking at his backside which suggested immense strength but little distinction…

Churchill’s self-satisfaction at a successful meeting was short lived. While he thought he had managed to divert Stalin’s request for a second front with his plans for the bombing of Germany and new offensives in French North Africa, it became clear the next day that a night of reflection had allowed Stalin to realise he was being offered little.

Stalin railed against Churchill’s failure to supply what the Soviets asked, citing the huge sacrifices made by the Russians on the eastern front. Churchill wrote to Attlee that Stalin had been very insulting:

I repulsed these squarely, but without taunts. I suppose he is not used to being contradicted repeatedly, but he did not become at all angry or animated. He kept his eyes half closed, always avoiding mine, uttering at intervals a string of insults…

Churchill stumped his interpreter by allowing a full-blown row to ensue (which it is difficult not to believe on some level both men enjoyed).

The next day – 14 August – was to have been a state banquet in the Kremlin, but when Clark Kerr went to Churchill’s dacha he found – every ambassador’s nightmare – that the prime minister was in a foul mood and refusing to go. He succeeded in getting him there, but Churchill insisted on wearing his siren suit – his wartime onesie designed to mimic the boiler suits of British workmen. The Soviets were in full regalia, Churchill in full sulk, leaving Stalin flailing with jokes and toasts before Churchill left early.

For Clark Kerr, this was a disaster. Back at the dacha, he reckoned with a petulant Churchill who wished he had never come; eventually, he persuaded Churchill to muster the remnants of his personal charm and give Stalin one last chance.

The final meeting in the Kremlin, the next day, was intended to be a brief and private one. In the end, it lasted for seven hours and finished with a roast suckling pig in Stalin’s flat. Churchill told Stalin that he had come ‘with an earnest wish for personal understanding’ and, according to the Soviet record, Stalin replied that: ‘The fact that he and Churchill had met and got to know each other and had prepared the ground for future agreements, had great significance. He was inclined to look at the matter more optimistically.’ At the end of the evening, a joint communique was drafted by Clark-Kerr and Molotov, while Churchill was to conclude that: ‘I feel I have established a personal relationship which will be helpful.’

This was the sole face to face contact for either Churchill or Stalin until the Tehran Conference at the end of 1943. It is hard not to conclude these meetings in August 1942 shaped the way that Stalin and Churchill danced around each other from then on, and gained for Churchill an advantage in his relationship with Roosevelt.

Modern political leaders meet each other frequently at summits and state visits. One might make an assumption that it is harder to keep fighting someone you have met face to face, but there is no evidence for this. Vladimir Putin and Sergei Lavrov have now been around so long that they have the personal measure of decades of western leaders. Demonstrably it works the other way round – personal chemistry and the force of an argument is not a given. In the glare of the cameras, awkwardly chaperoned by Angela Merkel and Emanuel Macron, Zelensky met Putin for the first time in December 2019, but there was no understanding for the taking.

So to the question of whether – when one side conducts an outrageously hostile act – it is better to cut off relations or plunge into a meeting, there is no simple answer, not least because a state of enmity is a constant competition that each side shapes by every move until one is victorious. It may be that a personal connection increases the belief on the part of the optimistic leader that there is a deal to be done, and it may be that they are right.

Those who know their enemy best are in a better position to take the final decisive action. Often those charged with the role of emissary or mediator may see and understand more, not least those whose job is to provide intelligence on the real motives and intentions of the enemy. It is their role to tell the leader what the adversary really thinks, or really, really thinks. But an ambassador can also go native, be too keen for ‘a successful visit’, and intelligence might be wrong.

Sometimes adversaries are crippled by mutual misunderstanding. The effect of the severing of United States’ relationships with Iran in 1979 is enduring incomprehension; just as it is completely understandable to cut ties with an enemy, a natural consequence of such action is a reduction in the level of understanding and an increase in the chance of miscalculation or misinterpretation.

And what of our friends? It is often the case that less energy goes into understanding the nature of friendships than enmities; there is no correlation between an alliance between nations and a friendship between leaders. And there is a critical coda: friendships that break down lead to much stronger feelings of betrayal.