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A Discussion on the thesis that “Jus Post Bellum has broadened the scope of Just War

Theory too far”.

Just War Theory (JWT) has been dominating discourse concerning the morality of war

for the last hundreds of years. Today, jus ad bellum and jus in bello, regulating the beginning

and conduct of war respectively, are accepted principles for the evaluation of a just war, and

are, moreover, implemented in international laws. However, the addition of a third category

to the theory, namely jus post bellum, has become a significant feature of recent debates. This

new set of principles is supposed to provide moral guidance for the end of a war in order to

create a just peace. Nevertheless, it is unclear if JWT needs to be reconceptualised: would a

third category of principles contribute to the validity of this theory, or would it broaden the

scope too much and thereby rendering JWT too demanding a theory to be implemented in

war and its aftermath?

This essay will argue that jus post bellum is a necessary enhancement of JWT and thus

makes the theory complete. Modern conflicts, such as the Afghanistan and Iraq wars show

that one must go beyond discussions on the moral beginning and conduct of war. In order to

decide whether a war is just or not, one must establish conditions concerning the legitimacy

of peace that follows the armed conflict. The traditional JWT is lacking with regards to the

post-conflict setting, and creates a normative vacuum which results in uncertainty.

Consequently, a post-war setting without moral restraints, and a clear set of obligations for

the belligerents, bears the potential for future conflicts. Jus post bellum fills this normative

gap by creating principles for a just peace and hence decreases the occurrence of just wars.

Consequently, the maximalist concept of jus post bellum will be used in the following

to demonstrate the necessity of jus post bellum since the minimalist approach does not push

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the boundaries of JWT enough, merely providing restraint for victors in the aftermath of war

and ignoring potential responsibilities and duties (Bellamy, 2008). Therefore, the maximalist

approach to jus post bellum is more suitable to exploring the contribution of jus post bellum

to JWT since it argues that the victor of a war has a moral and legal obligation towards the

defeated belligerent in order to create just peace: only if the victor fulfils his duties, can he

call himself a just belligerent (ibd.). Accordingly, a presentation of the jus post bellum

principles, consisting of a summary of concepts by several moral theorists such as Orend,

Evans and Walzer, will form the first part of this study, before subsequently examining the

correlation between a just war and a just peace. Further to this, the tension between a JWT

which might be too morally demanding to be implemented, and the necessity for a

comprehensive set of principles for just wars, will be discussed. Finally, jus post bellum´s

flexibility to adapt to the victor’s capabilities and to the local circumstances of the defeated

country, whilst still upholding universal moral principles, will be presented in order to

demonstrate that jus post bellum is not only applicable to every post-war situation, but is also

vital to a just peace.

To date, there is no definite list of principles which is shared by all moral theorists

concerning the multiple jus post bellum criteria. However, jus post bellum concepts generally

agree on certain obligations of the victor in the post-war setting, the principles of which are:

reconstruction, rehabilitation, punishment and discrimination. Reconstruction means that the

victor has to rebuild destroyed infrastructure, and establish, or re-establish, institutions in the

defeated country (Orend, 2002; Österdahl et al, 2009; May, 2012). This principle is based on

the saying “you break it, you own it” (Lazar, 2012: 18), in other words, the victor accepts his

share in the destruction of the defeated country, and his responsibility to rebuild it. Inherent

to the criterion of rehabilitation is the concept of reconciliation, which acknowledges the fact

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that war creates powerful resentments which need to be addressed in the post-conflict period

to prevent further aggression in the future (Evans, 2009; Orend, 2002; Lazar, 2012).

Additionally, the victor has the right to establish a “minimally just regime” (Evans, 2008: 53),

namely to protect the population of the defeated country by providing a government and

laws. However, Bass (2004) argues that although it is necessary to establish just institutions,

this does not consequently mean that the society and political system have to completely

change. Rawls (1999) concurs, stating that a victor is obliged to protect the integrity of the

loser’s political community. Therefore, occupation according to jus post bellum can only be

just until the defeated state is capable of acting as a just sovereign. Moreover, changes in the

political system should not occur against the will of the population (Walzer, 2007; Lee, 2012).

The third principle punishment includes the punishment of jus ad bellum and jus in bello war

crimes, as well as compensation in the form of reparation. Jus post bellum advocates argue

that war crime trials should be conducted post combat in order to punish the leaders who

started the war, as well as the combatants of both warring parties, themselves responsible for

the violation of jus in bello principles, such as the non-discrimination between civilians and

soldiers (Orend, 2002; May, 2012; Walzer, 2007). Furthermore, reparations should be paid by

the state which caused the war in order to compensate the victims for the wrongful harm that

was done (Lazar, 2012). The intention of punishment is twofold: firstly, to make amends to

the victims of the aggression and secondly, to deter future aggressors (Bass, 2004).

Nevertheless, it should be noted that the punishment must be proportionate to the crime and

should not be used for revenge (Lee, 2012). The final principle, discrimination, connects jus

post bellum with jus in bello. May (2012) argues that there must be a differentiation between

“the civilians who suffer from war and mass atrocities […] and the leaders who took them to

war” (p.199) since it would be unjust to punish civilians for their leaders’ crimes. In short, jus

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post bellum requires that all these principles must be met to have a just war and finally a just

peace.

However reasonable these principles might seem, it can be argued that it is

unnecessary to add jus post bellum to JWT since jus ad bellum and jus in bello already refer to

the aftermath of war. The just cause in jus ad bellum, for example, requires the war to be

started with the intention of bringing it to a just end, ensuring a just peace (Österdahl et al,

2009). Therefore, belligerents are already restrained in the post-war period by jus ad bellum

and cannot exploit their victory to suppress the defeated country. Furthermore, it is unclear

whether a category that deals with the post-war period should be part of a theory that was

intended to engage with the morality of war fighting (Lazar, 2012). As Walzer (2007) states,

wartimes are exceptional circumstances which require exceptional moral standards;

consequently, once the war is over, states should return to the ruling moral principles prior to

the eruption of the conflict (Lazar, 2012). If one adds jus post bellum to the theory, JWT is

reconceptualised in such a way that it is no longer a theory about war, but about war and

peace. As a result, the purpose of JWT is changed.

Nevertheless, sustainable peace is the reason why the just belligerent fought the war

in the first place. Therefore, it is not enough to look at how a war is started, and how it is

conducted, but one has to consider the end of war to the same extent, especially since the

conditions for a lasting peace are laid down after the ceasefire (Österdahl et al, 2009). Even

though jus ad bellum implies a just peace, the traditional dualistic JWT does not cover the

period between the armed conflict and the rebuilding of peace (Lee, 2012). Consequently, a

war theory which does not specifically regulates the last phase of war is not comprehensive

and consistent (Orend, 2002). Furthermore, although justice is linked to all phases of war, only

a demarcation of the three categories allows a refinement of justice (Evans, 2009). In other

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words, even though JWT is about justice and war, it equally deals with justice and peace.

Hence, jus post bellum connects war and peace and makes JWT complete. Furthermore, the

traditional JWT does not acknowledge the fact that the official end of war is not always the

equivalent to peace (Stahn, 2006). Instead, post-war settings, such as in Iraq after the US

invasion in 2003, demonstrate that the aftermath of war can be chaotic and violent, and that

an unsuccessful, unstable post-war setting can make citizens doubt the justice of the war (ibd).

Similarly, the aftermath of humanitarian interventions, for example in Rwanda in the 1990s,

has demonstrated that the way in which a war ends is important because it sets the scene for

potential conflicts in the future (Orend, 2002). In cases of humanitarian interventions

especially, it cannot be just for the intervener to fight against a country in order to stop human

rights abuse, and then leave the victims of the genocide with their former abusers and

potential further torture and homicide. Therefore, it is necessary to have a set of moral rules

defining how to conduct the transition period to ensure a just peace (Orend, 2000).

Nevertheless, it could be countered that jus post bellum principles are based on the

assumption that the war victor is the just belligerent (Orend, 2002). But what happens if the

victor is the unjust aggressor? This would mean that jus post bellum could not be implemented

(Pattison, 2014), and it is further unclear how jus post bellum could make this war more just.

In addition, Pattison (2014) is of the opinion that is unreasonable harsh to ask victims of

aggression to take responsibility for the aggressor after the end of the conflict. According to

jus post bellum it is not the aggressor and violator of human rights who is post-conflict morally

duty-bound but the intervener or the agent who acted in self-defence (Stahn, 2006).

Specifically in the case of humanitarian intervention, the intervener spends money and risks

the lives of its soldiers on behalf of a foreign population. To regard this intervention as just

only if he stays in the defeated country, invests further resources in rebuilding the

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infrastructure, in establishing a new government, and even acts for some time as the

sovereign of the defeated state, is morally questionable. It should be enough for an

intervening state to conduct a humanitarian intervention and stop the violation of human

rights, and thereby fulfil the jus ad bellum and jus in bello criteria (Pattison, 2014). Moreover,

if states have to consider jus post bellum whilst deciding whether to initiate a humanitarian

intervention, they might eventually feel “less likely to go to the aid of another state that is

being oppressed, or worse yet that they will hesitate defending themselves from aggression,

thereby making the aggressor more likely to achieve its illegal and immoral objectives” (May,

2012:174). Ultimately, jus post bellum does not promote justice, but causes agents to falter in

waging just wars and thus, conversely, helps unjust belligerents. Furthermore, jus post bellum

outlines obligations and restraints but does not explicitly say when these are fulfilled. The

post-conflict situation in Iraq after 2003 shows that even ten years of occupation, restoration,

and development aid did not make the state stable (Pattison, 2014). Does the US thus have

an obligation to remain in Iraq until the country is completely safe and stable, even if this

necessitates hundreds of years of occupation? It is doubtful whether the financial pressure on

the victor can be called just. Moreover, realists warn that “perfect security” (Bass, 2004: 394)

does not exist, and that the reconstruction of the defeated state even increases the security

dilemma since the financial and moral commitment weakens the victor. Accordingly, jus post

bellum does not necessarily increase justice, but instead could promote injustice and

insecurity by putting too much emphasis on the victor’s obligations and not enough on the

loser’s responsibilities.

The aim of a just war is to create an environment in which states are more secure and

human rights are better protected (Stahn, 2006). In order to reach that goal, jus post bellum

offers more than guidelines: it provides the chaotic post-war period with a structure which,

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through the constraint of immoral actions and the provision of a clear sense of what needs to

be done and by whom, could save lives and resources (DiMeglio, 2005). In the immediate

aftermath of war, the defeated country is in a time of transition and this usually means that

institutions and the rule of law are in “a highly dysfunctional condition” (Freeman et al, 2008:

215). Apart from a destroyed infrastructure, returning soldiers need to be re-integrated into

society, and a broken society must be rebuilt (May, 2012). Furthermore, in most cases, the

defeated government either no longer exist or is so weak that it cannot fulfil its core functions

of protecting its citizens and providing security (Evans, 2009). Even in cases where the former

government is still in power, it is not reasonable to re-establish the status quo of the political

leaders who initiated the unjust war in the first place (Evans, 2008). Conversely, the just victor

is in a morally and materially superior position because, even if he is weakened by the war, he

has proven to be militarily stronger and to have met the moral requirements of JWT.

Therefore, the just victor is likely to be more suitable and capable of rebuilding the defeated

country than the former government. Moreover, the just victor has an interest in being

involved in the opponent’s development because a just peace, with reconciled states, is the

only way to protect the victor from future aggression (Orend, 2002). Being involved and in

control of the reconstruction increases the victor’s security. Part of this involvement might

include a temporary occupation and financial support, but only up until the defeated state has

a government which can act on its own and only if this does not jeopardise the victor’s own

state (May, 2012).

It is true that jus post bellum increases the burden on a just belligerent, which could be

interpreted as unjust. It is incongruous to ask a victim of aggression to care about the

aggressor and to make an effort to aid that nation responsible for the death of the victor’s

citizens and soldiers. But as LaCroix (1988) states “perhaps there never has been a totally just

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war. But then perhaps there never has been a totally virtuous person. Neither fact reduces

the usefulness of clarifying the standards involved or having them in the first place” (p.141).

In other words, moral agents always carry a bigger burden than unjust ones since they have

to achieve their goals within a tight moral framework (Bass, 2004): this conforms to the

concept of JWT. If a belligerent attempts to initiate a just war and conduct a war justly, then

it should be clear that a just peace must follow (Bellamy, 2008). Only if a just peace follows a

just war can the victor call himself just (ibd). To make the justice of war dependent upon the

aftermath of war might appear unfair since the just victor already proved his moral standing

before and during the war. But even just warring parties have to acknowledge that any

destruction, and every casualty during the war, affects their moral standing. Evans (2009)

states that “morally justified circumstances have nevertheless turned you into a killer […]

[which] is still a matter for deep regret” (p.153). Jus post bellum obligations towards the

defeated aggressor mean that the regret for the destruction and the loss of lives are

transformed into a sense of responsibility. By following jus post bellum principles the winner

of the war acknowledges his part in the war and commits himself to doing anything to preserve

peace (Evans, 2008). This acceptance is not equivalent to the admission of wrongdoing, but

rather to an awareness of the consequences of their actions (Evans, 2009). Subsequently, a

victor who violated the jus ad bellum and jus in bello principles cannot compensate the unjust

war by establishing a just peace. Indeed, it might be difficult to imagine an unjust victor trying

to conduct a just end of war, since unjust belligerents have proven to disregard moral

restraints in the other two phases of war (Lazar, 2012). Nevertheless, jus post bellum could

have an effect on unjust belligerents, too, and could decrease the amount of just wars

(Österdahl et al, 2009). Firstly, if the principles are implemented in international law, violations

of jus post bellum can be punished by the international community. Secondly, post-conflict

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principles could be a motivation for unjust countries not to go to war, or if they initiated the

war to fight such that it does not harm the “prospects of a just and durable pace after the

conflict” (ibd: 185). If political leaders have to face the prospect of a long-term commitment

to the opposing country, and could even be held judicially accountable for the conflict, for

example through the principles of war crimes trials, they might think twice about initiating a

war (May, 2012). Therefore, jus post bellum increases justice in the post-conflict setting and

limits the occurrence of just wars (Bass, 2004).

Nonetheless, it can be argued that jus post bellum makes JWT too demanding, since in

order for a war to be just it now has to meet three sets of criteria. The problem with a

demanding theory is that the more complicated it gets, the less likely it will be used for moral

guidance. Moral principles need to be reasonable in the first place, and implementable in the

second. Additionally, the principles of jus post bellum are still vague and although some

consensus can be found among moral theorists, such as Evans and Orend, each of them puts

emphasis on a different jus post bellum principle (Österdahl et al, 2009). The aspect of

occupation is, for example, an ambiguity in jus post bellum since it can be seen as a violation

of the defeated population’s right to sovereignty and self-determination (Evans, 2009).

Furthermore, the importance of war crime trials is a hot topic of debate since they could be

used as an instrument of revenge by the victor (Orend, 2002). Finally, compensation in the

form of reparation does not necessarily lead to a just, sustainable peace, but can be exploited

to burden the defeated society in a way that it can lead to the uprisings of another aggressive

government, like the Treaty of Versailles which contributed to the rise of the Nazis in Germany

(Bass, 2004). Therefore, adding jus post bellum to the JWT only complicates the theory and

renders it less likely to be implemented.

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Admittedly, moral considerations and principles are always multidimensional and

debated among moral theorists, and are not only a specific feature of jus post bellum, but are

intrinsic to jus ad bellum and jus in bello. Alone the fact that jus post bellum is a point of

contention indicates its relevance, and its importance of jus post bellum. It renders JWT too

demanding only if one expects a theory to present “clear cut answers to our moral questions

about war” (Evans, 2008: 554). Jus post bellum principles are not simply constraints and rules:

they serve to guide moral actions. If they are interpreted too rigidly, as a list of items that need

to be ticked off, they might indeed become too demanding (ibd). The concept of jus post

bellum, however, takes into account that there are multiple versions of post-war scenarios.

Hence, “the demands of jus post bellum will vary from situation to situation and any general

statement needs to respect that fact” (Evans, 2009: 155). This does not mean that one

principle can be disregarded in favour of another, but rather that principles such as

discrimination between civilians and combatants with regard to punishment, human rights,

reconciliation, support and reconstruction are indisputable for a just peace (Österdahl et al,

2009). Nevertheless, jus post bellum is in fact not devoid of some flexibility. It is important to

be aware firstly of the specific needs and cultural backgrounds of the defeated population

(ibd), and secondly of the capabilities of the just victor (Patterson, 2012). For clarification, the

principle of reconstruction will serve as an example. According to jus post bellum, the victor

should care and have a sense of responsibility for the defeated country’s reconstruction since

he was involved in the battles that led to death and destruction (ibd). Nonetheless, this does

not necessarily mean that the just victor alone has a duty to reconstruct the defeated country.

Jus post bellum allows a trade-off between the victor’s capabilities and his obligation towards

the defeated country, and differentiates between responsibility and duty. Patterson (2012)

illustrates this by stating that “[…] the United States or European Union need not go bankrupt

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to make provisions for a reconstruction of Afghanistan or Kosovo, because their first priority

must be the lives and livelihoods of their own population” (p.223). Accordingly, DiMeglio

(2205) argues that responsibility might lie with the just victor, but local leaders, non-

governmental organisations, and other states could form a coalition to pool resources since

they all have an interest in a just peace, and consequently in establishing the former aggressor

as a valuable member of the international community. This argument conforms to the

cosmopolitan view that all states have a moral duty to protect human lives, and thus to

establish a stable and secure post-conflict state which can fulfil this obligation (Pattison, 2014).

This example shows that even though the principle and its purpose are unchangeable, jus post

bellum accounts for context in the process of implementing the principle (Orend, 2002), since

just peace does not depend on those who carry out a duty, but those who are responsible for

setting the process in motion and protecting the interest of those in any way harmed by the

war (Stahn, 2006). Thus implementing jus post bellum is both valid and renders JWT more

practical, connecting moral theory to complicated and diverse reality.

In conclusion, jus post bellum does not overly broaden the scope of JWT: on the

contrary, the flaws of the theory are compensated by a maximalist set of principles for the

aftermath of war. Although JWT traditionally already favours a just war, and jus ad bellum

implies a restraint in the post-conflict setting, a definite set of jus post bellum criteria is

necessary to provide the belligerents with post-war guidance. It is not enough to create a

negative peace and to prevent the just victor from exploiting his superior position following

ceasefire. Given that, as previously demonstrated, the aftermath of war bears the potential

for future conflicts or for a sustainable peace, in order to achieve the latter, the just victor

must have a sense of responsibility and obligations. Critics should acknowledge that the jus

post bellum debate is still in its infancy, and hence jus post bellum principles are still vague in

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their formulation. However, jus ad bellum and jus in bello have had the benefit of hundreds of

years to be refined, and thus it is to be expected that jus post bellum must be discussed

further. Therefore, more research and debates must be conducted in order to ensure that the

aftermath of war is structured in a way that prevents future conflicts. Jus post bellum as part

of JWT provides a framework within which this discussion can take place. Ultimately, the

enhancement of JWT will have legal and political implications, and will therefore have a

positive influence on the justice of war.

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