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The Quality of Mercy: Morality and the Interest of the State

  • Published
  • By Laura Russell

The quality of mercy is not strained; 
It droppeth as the gentle rain from heaven 
Upon the place beneath. It is twice blest; 
‘T is mightiest in the mightiest; it becomes 
The throned monarch better than his crown… 
The Merchant of Venice  
Act IV, Scene 1 
William Shakespeare 


Is it in the interests of a state to behave morally?  According to Niccolò Machiavelli, an Italian diplomat and political theorist, “a ruler who wishes to maintain his power must be prepared to act immorally when this becomes necessary” (The Prince, cp. XV).  There’s truth to align with this argument in both principle and history – but immoral behavior is neither the only nor the most effective means for a ruler or state to achieve their best interests.  Based on the following analysis of Thucydides’ Peloponnesian War, given equivalent circumstances, a state that has the ability to act mercifully is better equipped to maintain power than a state which is prepared to act immorally.   

Before analyzing four examples from Thucydides, we should first look at the context of Machiavelli’s assertion and consider how this impacts our understanding of both “interest” and “moral behavior.”  Machiavelli prefaced his argument with a broader observation on human nature: “my hope is to write a book that will be useful, at least to those who read it intelligently, and so I thought it sensible to go straight to a discussion of how things are in real life and not waste time with a discussion of an imaginary world.  […] For anyone who wants to act the part of a good man in all circumstances will bring about his own ruin, for those he has to deal with will not all be good” (The Prince, cp. XV).  A key point here is that the morality demonstrated by a ruler is defined by the morality demonstrated by those with whom he deals.  The necessity of immorality for which Machiavelli advocates, in other terms, is defined by an opponent’s behavior or anticipated action.  While we can accept Machiavelli’s premise that maintaining power is in the interests of a state, there is more than one means to this end.  Particularly when a nation is acting from a position of power, what provides more leverage over the behavior of an opponent: the ability to obtain cooperation through mercy, or the ability to maintain deterrent force through immoral action?  

Towards the definition of interest, I submit that it is comprised of at least the following: the ability to maintain power in a rapidly evolving multipolar political ecosystem which requires collaboration more frequently than conflict to achieve an end. Given this definition, consider the following propositions: it is in a state’s best interest to cultivate international respect and leverage in order to maintain power; this international respect is best cultivated through moral behavior by a more powerful state; and when a state is in a position of power, morality is frequently characterized by mercy.  Perhaps Portia captured it best when she highlighted the importance – or, in Machiavellian terms, the consequent power or “might” – of combining justice with mercy in The Merchant of Venice.  While her observation that “in the course of justice, none of us/Should see salvation” springs from a particular worldview and culture, it nonetheless tugs at a truth which transcends worldview and culture (Shakespeare, Act IV.1).  Whether we look at the microcosm of human relationships or the macrocosm of international relationships, the impossibility of maintaining power and stability without some degree of metaphorical “give” and the willingness to assume some degree of good intent is self-evident.  It is less a question of if powerful states should behave morally, but how – a question to which Thucydides may have the answer.   

The first case study for this question occurs in Book III of Thucydides’ Peloponnesian War, in which Cleon and Diodotus debate whether Athens should execute the Mytilenians as a consequence of the latter’s revolt.  Cleon emphasizes the importance of a swift and merciless execution, as the three failings fatal to an empire are “pity, sentiment, and indulgence” (3.40).  These three failings share many characteristics with the concept of mercy, differing primarily in execution.  Although he argues separately for the justice of punishing the Mytilenians, Cleon also aligns himself with Machiavelli by emphasizing the necessary sacrifice of morality in order to maintain power: “if, right or wrong, you determine to rule, you must carry out your principle and punish the Mytilenians as your interest requires; or else you must give up your empire and cultivate honesty without danger” (3.40).   

In contrast, Diodotus supports sparing most of the Mytilenians, arguing that the interests of Athens and the question of justice are separate issues.  He focuses the attention of his audience on how to make the Mytilenians useful to Athens without addressing what a just course of action would be (3.44).  This could be interpreted as a deliberately amoral and Machiavellian argument.  However, in doing so, Diodotus also removes any rhetorical opportunity for Cleon to incite the emotions of their audience by highlighting how the Mytilenians wronged the Athenians.  It is entirely possible that Diodotus believed sparing the Mytilenians was not only expedient, but also moral – this would simply have been a less effective argument.  Diodotus also observes that to “butcher” the Mytilenians would damage Athens’ relationship with her other allies and create opportunities for her enemies (3.47).  Or, in other words, obtaining cooperation through mercy is a more effective way to maintain power than using immoral action as a deterrent force.   

A second example of the arguably immoral use of power occurs in Book IV, after Athens defeats Sparta at the battle of Pylos.  Sparta makes the argument for a merciful peace to promote reciprocity: “indeed if great enmities are ever to be really settled, we think it will be not by the system of revenge and military success, and by forcing an opponent to swear to a treaty to his disadvantage; but when the more fortunate combatant waives his privileges, and, guided by gentler feelings, conquers his rival in generosity and accords peace on more moderate conditions than expected”  (4.18).  Had Sparta made this argument when they were the more fortunate combatant, it would be less vulnerable to criticism.  However, reciprocity is a powerful dynamic, whether between individuals or nations.  It is difficult not to hear an echo of Sparta’s argument in Shylock’s famous speech: “If you prick us, do we not bleed?  If you tickle us, do we not laugh?  If you poison us, do we not die?  And if you wrong us, shall we not revenge?” (Shakespeare, III.1).  Vengeance drives revenge in a vicious cycle.  Because the Athenians rejected these terms, the peace established was nothing more than an intermission between direct conflicts.  The subsequent historical events prove the accuracy of Sparta’s argument. 

As a third case study, consider the series of arguments in Book V, when the Melians unsuccessfully attempt to negotiate favorable terms with the Athenians based on the concept of justice.  In response to the Melians’ argument that they are “just men fighting against unjust,” the Athenians flip the script and suggest they are merely engaging in a pursuit of authority which is common across mankind: “we found it existing before us, and shall leave it to exist forever after us” (5.105).  Had Athens won the war in question, this would have been an effective piece of evidence for Machiavelli’s argument.  As is, we are left to question whether the Athenians’ emphasis on power which lacked both justice and mercy was not a harbinger of their eventual defeat.  In addition, embedded in this quotation is a gesture toward the inevitability of turnover and loss of power when it is defined by immoral action: for the Athenians to leave the dynamic to exist “forever after us” suggests that there is a time after.  Over the short term, Athenians have a degree of power which enables them to behave as they will – but the choice to behave as they will places an expiration date on this power.  This is the practical result of vengeance driving revenge.  The Athenians’ implicit abandonment of human responsibility and autonomy in the moral sphere remains unaddressed by the Melians.  In contrast to the debate between Diodotus and Cleon, by accepting the amoral logical framework, the Melians leave themselves no opportunity for rhetorical victory.   

Fourth and finally, consider the Spartan logic for the invasion of Attica in Book VII.  After considering many events over the course of the war, including the Athenians’ behavior at Pylos, the Spartans decide that Athens “had become the guilty party; and they [the Spartans] began to be full of enthusiasm for the war” (7.18).  A nation’s belief that they possess the moral high ground can be a powerful motivator.  Had Sparta not perceived Athens as the violator of the truce, and therefore an immoral actor, they might not have opened a war on the second front.  This was a key step toward Athens’ eventual defeat. 

Returning to Machiavelli’s original argument: the idea that declining immoral action will bring about a nation’s ruin is powerful.  Where is the line between morality and naivete?  It is certainly true that not every nation-state actor will behave in a moral manner.  As the behaviors and emotions of states reflect the individuals who have achieved or been placed in positions of power and public prominence, frequently a nation’s immoral action reflects an individual’s flaws.  However, if we lean into this idea a little further: if we accept that some states will act in an immoral manner, what is the most effective way to preserve our own power?  If we wield power immorally, will we not – as Diodotus suggests – drive our allies toward our enemies?  Choosing to act with mercy and generosity is a long-term investment that comes at a short-term price.  This behavior both requires power and allows for its preservation.   

In conclusion, I concur with Machiavelli that the preservation of power is a key interest of the state.  However, choosing to preserve this power via immoral means is a short-term solution with long-term negative consequences.  As we see across multiple case studies in the Peloponnesian War, choosing to wield power without regard for moral considerations drives conflict, and conflict will at some point drive defeat.  In Machiavelli’s world, because his very conception of power depends on conflict, nations are destined to rise and fall.  However, if we allow for a different conception of maintaining power – defined in terms of moral behavior – perhaps power can be characterized by continuity instead of conflict.  In other words: since those who he deals with will not all be good, a ruler who wishes to maintain his power must be prepared to act not with immorality, but with mercy.  

Ms. Laura Russell

Ms. Laura Russell is a civilian assigned to the Department of the Air Force.  She completed ACSC in January 2022 

Selected Bibliography  

Machiavelli, Niccolò; ed. Wootton, D.  The Prince. Indianapolis, IN: Hackett Publishing Company, Inc., 1995.   

Shakespeare, William. The Merchant of Venice. New York, NY: Penguin Group, 2000. 

Thucydides; ed. Strassler, R. B., & Crawley, R. The Landmark Thucydides: A Comprehensive Guide to the Peloponnesian War. New York, NY: Simon and Schuster, Inc., 2008.   


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