Poland is again threatened by a tyrant. This time, Europe must not look away | Simon Tisdall

Donald Tusk needs to convince European leaders to act to deter Vladimir Putin from further aggression

Recent panicky talk of a third world war seems a tad overblown. Yet the specific threat posed by Russia's aggressive, revisionist regime to eastern Europe is real and growing. As in the past, Poland is on the frontline of a battle for Ukraine that could easily spread. Scrambling to shore up defences, the UK and European Nato states must decide: is this 1920 or 1939?

As all Poles know, the Battle of Warsaw, 104 years ago this August, ended in Marshal Jozef Pisudski's famous victory over the invading Red Army, which secured their country's independence. They called it the Miracle on the Vistula", after the river linking Poland's main cities. Vladimir Lenin lamented an enormous defeat" for Bolshevik revolutionary ambitions in Europe.