“Conquests are easily made, because we achieve them with our whole force; they are retained with difficulty, because we defend them with only a part of our forces,” says Montesquieu in context Hannibal's failure in defending his territory against Rome.
Montesquieu points out that whenever Hannibal could keep his army together, he defeated the Romans. But when he was obliged to put his garrisons into the cities to defend allies, to besiege strongholds, or to prevent their being besieged, he found himself too weak, because in such situations much of his army used to melt away.
Hannibal was a great general, but his Carthagian army was not disciplined and his soldiers were mostly mercenaries—they had little incentive to fight unless they saw a scope for enriching themselves from the spoils of war.
Rapine was common among the Romans too. Montesquieu says that Rome being a city in which neither trade nor arts flourished, rapine was the only way by which the citizens could enrich themselves.
But there was a degree of discipline in the Roman method of plunder. The Roman generals did not allow their forces to embezzle anything. The plunder was done in a systematic way, and everything that was looted was accounted for. When the war was over the Romans would distribute the loot and every fighting man would get his share.
The Considerations is primarily a book of history, but it contains lot of insights on political theory because Montesquieu has peppered the narrative with his political philosophy.
He employs a brilliant aphoristic style in presenting his ideas. In the first chapter, he says, “At the infancy of societies, the leading men in the republic form the constitution; afterwards, the constitution forms the leading men in the republic.”
The conflict between the intellectual Cicero and the warrior Mark Antony is interestingly narrated by Montesquieu. Cicero helped Octavius in defeating Antony. Montesquieu points out that Cicero liked to boast that his robe had crushed the arms of Antony.
Octavius shrewdly played on Cicero’s vanity. “Octavius, in his conduct to Cicero, acted like a man who knew the world; he flattered, he praised, he consulted him, and employed every engaging artifice, which vanity never distrusts.” Eventually Octavius turned out to be a formidable enemy of Cicero’s liberal political ideas.
Comparing Cicero with Cato, Montesquieu says, “Cicero always thought of himself first, Cato always forgot about himself. The latter wanted to save the republic for its own sake, the former in order to boast of it.”
Montesquieu blames Mark Antony for his lack of understanding of human nature. Antony used to think that by raising people in life and lavishing them with wealth he could win their everlasting loyalty. But in the end he was betrayed by his closest generals and kings. Even Cleopatra, the woman for whom Antony had made many sacrifices, betrayed him. Montesquieu cynically remarks, “Load a man with benefits, the first idea you inspire him with, is to find ways to preserve them; they are new interests which you give him to defend.”
Octavius reigned as Augustus and he diminished the Roman institutions. He marginalized the Senate and became a dictator of Rome. His conduct paved the way for a slow and steady decline of the Roman Empire.
On Caligula, Montesquieu says, “Caligula was a true sophist in cruelty, for as he equally descended from Antony and Augustus, he declared he would punish the consuls if they celebrated the day appointed to commemorate the victory at Actium, and that they should likewise feel his severity if they neglected to honor that event; and Drusilla, to whom he accorded divine honors, being dead, it was a crime to bewail her because she was a goddess, and as great an offence to forbear that sorrow because she was a sister.”
With a few exceptions the Roman emperors who followed Augustus were men of low calibre, and they led to a steady degradation in the affairs of Rome. There came a time when the Empire could not defend itself against the barbarians. Montesquieu informs that Attila was charging the Romans a tribute of two hundred thousand pounds of gold.
History of the Decline and Fall of the Roman Empire by Edward Gibbon sprawls across 3000 pages, whereas Montesquieu’s Considerations is of just 250 pages. Gibbon packs a lot of historical detail in his work, but Montesquieu, the philosopher of the Enlightenment, provides a better political analysis. In my view, Montesquieu’s book can be seen as a good condensation of Gibbon’s work.