I have written before about the power of unpredictability to deter tyrants. With a second presidency of the notoriously capricious Trump in prospect, it’s perhaps worth expanding on those remarks.

During Cold War 1, it was arguable that the predictability of American response to hostile activities was a key factor in deterrence. Since 1975, America’s willingness to respond robustly and punitively to transgressions has been decreasingly predictable. Obama did much to accelerate this decline, setting a succession of ‘red lines’ which he failed to defend when they were crossed. Tellingly, this included a flaccid response to Russia’s invasion of Crimea in 2014.

Trump’s presidency did something to reverse this decline, and it is no coincidence, as the Donald himself has boasted, that Russia made no further incursions while he was in charge.

Then came the catastrophe of Biden, and his abject scuttle from Afghanistan. By the time of Russia’s full-scale invasion of Ukraine, American predictability had come to imply, at best, a storm of rhetorical posturing, at worst outright passivity. We are now in Cold War 2, and the road back to effective deterrence is a long and arduous one. Unlike Cold War 1, however, the direction of travel dictates that unpredictability of American response is a key virtue, not a shortcoming.

Trump is a deeply unattractive personality, but only the irredeemably juvenile elect their leaders because they are nice people. A fair assessment of his first presidency (not that the chattering classes will ever give him one) would give him high marks for geopolitical achievement. His unpredictability must account for much of this success. Those who point to his chummy remarks about Putin as evidence that he will sell Ukraine cheaply neglect, not just his unpredictability, but the old adage about keeping one’s friends close, and one’s enemies closer.

In one respect, however, Trump is utterly predictable. He will do whatever he believes will flatter his legacy. Should he win the forthcoming election, the task of those around him, indeed, of anyone keen rescue liberal democracy from the tyrants who threaten it, will be to persuade him that what is good for the Western world is good for Trump. He is clearly no lover of China, nor an apologist for its leaders. Persuading him that convincingly defeating Russia in Ukraine will greatly strengthen his hand in dealing with Chinese ambition, and will be far less expensive than fighting it out in the South China Sea should not be hard, for anyone prepared to look beyond his loutish persona, and focus on outcomes.