A Greater than Napoleon by Sir Basil Henry Liddell Hart

With Cartagena in his grip, Scipio had gained the strategical initiative, which is by no means identical with the offensive. To attack the Carthaginian field armies while he was still markedly inferior in numbers would be to throw away this advantage and imperil all that he had gained. On the other hand, he held the key to any possible Carthaginian move. If they moved to regain Cartagena, itself impregnable if adequately garrisoned, and still more so when the defender had command of the sea, he lay on their flank with his main striking force. If they moved against him, he would have the advantage of choosing his own ground, and, in addition, Cartagena would threaten their rear, for his command of the sea would enable him to transfer forces there. If they remained passive, and this inaction proved their choice, they would suffer the handicap due to the loss of their base, depot, and main line of communication with Carthage. Nothing could have suited Scipio better, for the respite allowed the moral effect of Cartagena's capture to sink into the minds of the Spanish, and allowed him also time to win over fresh allies to offset his numerical handicap. The result proved the soundness of his calculations, for during the next winter Edeco, Andobales, and Mandonius, three of the most powerful chieftains in Spain, came over to him, and most of the Iberian tribes followed their example. As Polybius justly says, "Those who have won victories are far more numerous than those who have used them to advantage," and Scipio, more than any other great captain, seems to have grasped the truth that the fruits of victory lie in the after years of peace-a truth hardly realised even to-day, despite the lessons of Versailles.

The outcome was that Hasdrubal Barca, faced with this shifting of the balance, felt forced to take the offensive. This gage Scipio, thus reinforced, was not loth to accept, for it promised him the chance to deal with one hostile army before the others had joined it. But with the principle of security impressed on his mind, he still further strengthened his forces, to meet the possibility that he might be forced to fight more than one army at once. This he did by the ingenious measure of hauling his ships on shore at Tarraco and adding their crews to his army, a course which was feasible because the Carthaginian ships had been swept from the sea, and because he was about to advance into the interior. His foresight in exploiting the workshop resources of Cartagena gave him an ample reserve of weapons from which to arm them.