I think that Adrian Goldsworthy is the best popular historian on Rome working today. While he has a beautiful writing style, he also is thoroughly versed in the scholarly issues, which he brings into the discussion without the excesses of academic proofs and oneupmanship. It is a very difficult balance to strike and the author does it to perfection. This book is at the undergraduate level, for those seriously interested in the three Punic Wars. Rather than make comparisons with the present, the author's purpose is to explain the wars in historical context, from a strictly military point of view; in this way, to his great credit, he refuses to make fatuous generalizations of relevance to the twit pundits who have way too much to say about things they know way too little about.
The book starts off pretty dry, with a long discussion of the states of Carthage and Rome at the time that the conflict began. While I was very interested in the political systems of both states and the tidbits that Goldsworthy includes on their civilizations, his dissection of their military machines was a bit too much for me. The Romans relied primarily on a reservoir of manpower from farm owners in Italy, which included extremely loyal Latin and Italian allies in addition to some Spanish mercenaries. They were driven by patriotism, were governed in accordance with the yearly elected consuls of the Republican system, and were essentially amateur soldiers. With their reservoir of human capital, their great advantage lay in the application of overwhelming brute force, which they applied until their adversaries were exhausted. Politics was inextricably linked to military action, though the consuls were patrician aristocrats seeking glory for parochial political motives and hence also military amateurs. Up to this point, there was little refinement or subtlety to their tactics and diplomacy.
In contrast, the Carthaginians had a dispersed empire that spanned the western Mediterranean in a C-shape. There was a core of Carthaginian aristocrats that controlled all of the myriad ethnic groups under their influence, mainly for purposes of trade - mostly maritime - and only secondarily for military use; they excelled at nuanced diplomacy and negotiation. In addition, there was a caste of professional military officers, who managed a huge mercenary army and various allies that operated in relatively separate units (i.e. wings even in a common army, which fundamentally effected their cohesion). With their experience from an early age, the military leader caste operated more from intelligent tactics and highly developed specializations, in particular in naval maneuverability, the use of elephants to overawe their adversaries on land, and flexible military formations.
The first Punic War broke out over control of Sicily, which was a patchwork of Carthaginian, Greek, and Italianate city states. After many indecisive skirmishes, Rome sent troops - the first time they left the Italian peninsula! - and built its first navy. In time, after many disasters, some natural others via lack of experience, the Roman navy beat Carthage by attrition as did the Roman Army. Carthage sued for peace, agreed to pay massive indemnities (which they did), and gave up Sicily and many other possessions for the promise of peace as subordinates.
Hannibal, of the Barca military clan, was assigned Spain, which he consolidated for Carthage to the growing disquiet of Rome. It was clear from the outset that he was an extraordinary military talent, though little is known about his character or psychology, though his motivation was to weaken Rome as a prelude to negotiation rather than destroy it. As tensions built, in 218 BCE - after more than 20 years of peace - at 26 years of age, Hannibal moved a massive army across the Alps into Italy, an unprecedentedly massive movement of troops, complete with elephants, and attacked Rome at its heart. He gathered many followers along the way (in a scale of tens of thousands, of SPaniards and Gauls, but, significantly, rarely of Latins or Italians) that he had to feed, arm, and inspire. This he did by winning early significant victories, ravaging the countryside, and stealing what he could while vainly attempting to recruit southern Italians.
The Romans had never faced such a threat, from a strategist and leader of genius who adapted his tactics to their weaknesses, e.g. Cannae, where he enveloped and attacked from behind a massive Roman phalanx that could only march forward and hence unable to regroup and reform, resulting in a slaughter of nearly 50,000 Romans, or 1/10 of the entire potential military manpower in Italy. In all later military literature, Cannae became a touchstone noun. Against their military culture, the Romans voted in a dictator for 6 months, Fabius Maximus, who harassed but would not engage Hannibal in any decisive battles (named the Fabien strategy). It bought Rome time to regroup and attack in N. Africa, once again bringing its adversary down by superior force. Never defeated in Italy, Hannibal had been ordered to defend Carthage - his only failure - and was exiled soon after the defeat. Rome emerged with a far better trained army under its own military genius, Scipio. This was the true beginning of the Roman Empire. The third Punic War was shamefully manufactured by Rome and consisted of a siege of Carthage, which was completely destroyed in 146 BCE.
The difference between the 2 Empires was that, contrary to the expectations of Carthage, Rome regarded the fight as one to the death: the Roman republicans refused all compromise and instead of giving up, resolved to fight on no matter what the sacrifice, even at the risk of total destruction. This explains why in the end, when they had the means in spite of Carthage's behavior as a good subordinate power, the Romans resolved to annihilate any rival power. Rome then went on to completely dominate the entire Mediterranean, the undisputed power of the ancient world for the next 600 years or so, in large part from what it learned from the conflict with Carthage. This is military history at its absolute best.