The limits of treating war as an attrition equation

German U-boat planning is criticized for setting a shipping-loss target without adequately accounting for British replacement construction. The wider objection is that prewar analysis rarely considered how Britain would respond to the German plan. An expectation of short wars compounded that weakness because British resistance could continue long enough for production and countermeasures to change. The discussion extends the earlier criticism of Vietnam's body-count strategy: a numerical target can leave out the decisions that determine whether the opponent keeps fighting.