The standing army which Annibal left behind him in Spain, had the like superiority over the militia which the Romans sent to oppose it, and in a few years, under the command of his brother, the younger Asdrubal, expelled them almost entirely from that country.
Annibal was ill supplied from home. The Roman militia, being continually in the field, became in the progress of the war a well disciplined and well exercised standing army; and the superiority of Annibal grew every day less and less. Asdrubal judged it necessary to lead the whole, or almost the whole of the standing army which he commanded in Spain, to the assistance of his brother in Italy. In this march he is said to have been misled by his guides; and in a country which he did not know, was surprised and attacked by another standing army, in every respect equal or superior to his own, and was entirely defeated.
When Asdrubal had left Spain, the great Scipio found nothing to oppose him but a militia inferior to his own. He conquered and subdued that militia, and, in the course of the war, his own militia necessarily became a well-disciplined and well-exercised standing army. That standing army was afterwards carried to Africa, where it found nothing but a militia to oppose it. In order to defend Carthage it became necessary to recall the standing army of Annibal. The disheartened and frequently defeated African militia joined it, and, at the battle of Zama, composed the greater part of the troops of Annibal. The event of that day determined the fate of the two rival republics.