Motorised infantry of the German armed forces (Wehrmacht) advancing into Ukraine during the invasion of Russia in the second World War. Photograph: Hulton Archive/Getty Images Germany has a unique historical responsibility to help defend a free and sovereign Ukraine. Europe’s central power is also uniquely qualified to shape a larger European response designed to end Vladimir Putin’s criminal war of terror in a way that deters future aggression around places such as Taiwan. As a signal of strategic intent to measure up to this double obligation, from the past and for the future, the Berlin government should commit at the...