The great nightmare of the Cold War was that giant Russian tank armies would not only crush their immediate neighbours but also sweep across the north German plains, hug western cities like Hamburg and hold them hostage, confounding all our calculations about a cautious escalation ladder. Now we have promised to supply Ukraine with a Nato tank army, there is a new version of this bad dream: is the war set to run out of control? It is difficult to see the relatively small number of pledged tanks matching their billing of becoming a game changer. At the Battle of...
