A hundred miles advance with such an enormous front as
theirs means, even apart from the wastage of war, a loss of two hundred thousand men in masking fortresses and guarding lines of communication. In an enemy's country lines of com- munication must be held with the iron grip of numbers. Not a railway bridge, not a railway culvert, not a road or river must be left unguarded. That would be a disadvantage to the Germans, as they found it in 1870, even if there were no anxieties behind them. But if the Germans have to bring back half a million men from the southern theatre of war to the north, -what then? The traversing of that hundred miles of enemy's country may prove a terrible anxiety. The French and the British have only got doggedly to pursue a Fabian defensive strategy (though, of course, an alert tactical offensive) to make the German position week by week more and more difficult.
