Masinissa, a brilliant Numidian cavalry commander crucial to Carthage's early successes, was not driven by ideology. After Scipio decisively defeated the last Carthaginian army in Spain, Masinissa pragmatically switched his allegiance to the Romans, recognizing they now held the momentum and offered a better path to power.

After Cannae, Rome couldn't defeat Hannibal in open battle, so they adopted a strategy of avoidance, creating a stalemate. For a power on the brink of collapse, simply surviving is a form of victory. This prolonged timeline allowed Rome to regroup, rebuild its manpower, and ultimately go on the offensive.

The Roman war in Spain was less about territorial conquest and more a strategic effort to stop reinforcements from reaching Hannibal in Italy. By engaging Carthaginian forces under Hasdrubal, the Scipio brothers tied down critical enemy armies and resources, preventing Hannibal from receiving the support needed to win.

After Cannae, Rome desperately needed manpower, yet the Senate refused Hannibal's offer to ransom its captured soldiers. This seemingly counterintuitive decision was a powerful psychological statement to Hannibal, their allies, and their own people: there would be no negotiation, only total war, regardless of the human cost.

After losing Sicily, the Carthaginian general Hamilcar Barca and his son Hannibal didn't try to reclaim it directly. Instead, they built a new, resource-rich empire in Spain. Its vast mineral wealth funded a mercenary army, turning Spain into a formidable base from which to launch a revenge war against Rome.

While battles like Cannae are famous, the Roman victory at Iberra in 215 BC was arguably more critical. By stopping Hannibal's brother Hasdrubal from reinforcing him in Italy just after Rome's greatest defeat, the Scipio brothers prevented a likely Carthaginian victory and changed the course of the war.

Scipio learned that a lagoon protecting New Carthage periodically became shallow. He timed his attack for this moment, presenting the ebbing water to his troops as a miracle promised by the god Neptune. This divine framing inspired his men and enabled a surprise attack on an unguarded wall.

The historian Polybius described the Roman sack of New Carthage, noting the practice of killing indiscriminately—including cutting dogs in half—was a deliberate policy. This was not random brutality but a calculated psychological tactic to inspire terror and ensure swift surrenders in future conflicts.

After his decisive victory at Cannae, Hannibal expected Rome to negotiate terms, as was the norm in ancient warfare. He fatally underestimated their unique, implacable resolve to never capitulate, causing him to miss his window of opportunity to march on the city and enforce a peace.