Cyril Connolly recalled the summer of 1938 in Enemies Of Promise as "the time of year when wars break out, and a piece of glass betrays the woodland to the vindictive sun". The vindictive sun then was Hitler's Germany; the pieces of glass, respectively, the Rhineland, Czech, Danzig and Polish crises. Today, though far from that world of looming catastrophe, there are disturbing similarities, especially in the way that the language of international diplomacy, first over Georgia and now over Poland, is threatening to careen dangerously out of control, embracing one country after another and locking the United States and Russia into a dangerous cycle of retaliatory threats.
Russia's announcement on Friday that Poland could consider itself a target for nuclear strikes in future opened up a new area of rhetorical conflict in a war of words hitherto confined to South Ossetia. Given Poland's bitter resentment of Russian domination, this brazen attempt to bully a sovereign state can only be judged provocative. But no sooner does Russia land its surprise punch on Poland than neighbouring Ukraine ups the ante. A day later, Ukraine's President, Viktor Yushchenko, weighs in with threats to cancel Russia's lease of the Crimean port of Sevastopol, if Russian ships there join the Georgia conflict.
As a contribution to lowering tension with Russia, this was deeply unhelpful. Ukraine's ambitions to join Nato agitate a Kremlin neurotically concerned with encirclement. The threat was also a risky move domestically on Yushchenko's part, given the fragile peace reigning in Ukraine between pro-Russian and pro-European forces and the strongly pro-Russian sentiment of the Crimea. If any area is likely to become the next Connollyesque piece of glass, betraying the tinder-dry woodland to the sun, it is Crimea.
Where to go from here? The Tory leader, David Cameron, clearly believes in landing punch for punch. Rushing into the waiting arms of Georgia's embattled leader, Mikheil Saakashvili, he declares sympathy for the doomed expedition into South Ossetia and urges a list of sanctions on Russia. This school of opinion, which holds that Russia must be "taught a lesson", is popular on both sides of the Atlantic. But the risk is that the woodland of Eastern Europe gets dryer and more combustible by the second and each and every area of disagreement between East and West takes on a dramatic new potential to trigger crises elsewhere.
Of course Russia needs to be rebuffed when it resorts to nuclear threats to dissuade Poland from signing up to Nato's missile defence shield – a ridiculous intervention to make now when Poland's intentions on this issue have been clear for years. As a Nato and European Union member, Poland is well out of Russia's sphere. Ditto the Baltic states, whose freedom was shamefully bartered away more than 60 years ago at Yalta. The Kremlin's penchant for bullying tiny Latvia and Estonia in particular needs to be answered, possibly more robustly than has been the case till now.
But beyond that, there is an argument for saying we need to pause for thought and stop trying to match blow for blow. We have to break this chain reaction, which encourages one country after another to pile into the South Ossetia dispute and take it off into a new direction.
We are in danger of forgetting that the real priority here is to sort out – and cool heads – in Georgia and its disputed enclaves, which means supporting the French-brokered ceasefire agreement, and urging both Russia and Georgia to honour its terms.