From day one of the war in Ukraine, the most powerful argument against unrestrained western intervention in the conflict has been the danger of catastrophic escalation into an all-out war between Nato and Russia.So far, western governments have shied away from a truly existential confrontation with Russia. But the threat remains that continuing western military aid to Ukraine will provoke Russian countermeasures that could turn Moscow’s proxy war with Nato into a direct military conflict.Western hawks have long argued the danger of escalation is illusory. In an op-ed for the New York Times, former British diplomat Nigel Gould-Davies claimed “Putin...