1. The use of force in international law
‘Just war’ to Article 2(4)

2. Overview
In this slideshow we will look at the ‘just war’ theory Why? Because ‘just war’ theory is arguably the philosophical foundation of the UN Charter’s limitations on the use of force. We will also look at Article 2(4) of the UN Charter Background reading: Shaw, M International Law 6th ed, pp

3. Definition - 1
“Just war” (in Latin Bellum iustum) is a doctrine of military ethics, of Roman and Catholic origin…which holds that a violent conflict ought to meet philosphical, relgious or political criteria
Source: Wikipedia, “Just War Theory”, (last accessed on 22 September 2013) .

4. Definition - 2
The Just War theory specifies conditions for judging if it is just to go to war, and conditions for how the war should be fought. Although it was extensively developed by Christian theologians, it can be used by people of every faith and none.
Source: BBC, Just War, Introduction, ml (last accessed 22 September 2013)

5. ‘Just war’
The theory or doctrine of the ‘just war’ is common to many different religions including Hinduism and Christianity
India: the ancient Mahabarata (circa 5th-2nd century BC) discussed when it is ‘just’ or right to wage war
The Mahabarata is an ancient Sanskrit text, part of Hindu religion
In it, there is a discussion between 2 brothers on when it is just to wage war
Many ideas were discussed which we recognise today, eg. proportionality (chariots cannot attack cavalry, only other chariots, no attacking people in distress), just means (no poisoned or barbed arrows), just cause (no attacking out of rage), and fair treatment of captives and the wounded
Just war theory came to be part of Western international law via the Christianisation of the Roman Empire

6. Augustine (354-430 AD) was able to do that
‘Just war’ continued…
Christian scholars such as Augustine of Hippo and Thomas Aquinas thought and wrote about when it is just (right) to wage war
Christians had to justify war in the face of the Bible’s apparent prohibition of war (ie “turn the other cheek” in Matthew 5:39)
Augustine ( AD) was able to do that
Thomas Aquinas ( AD) developed the idea further

7. Augustine of Hippo Born 354, died 430
Lived in Annaba, Algeria Used the phrase ‘just war’ in his book The City of God He said peacefulness in the face of a grave wrong that could only be stopped by violence would be a sin. Defense of one's self or others could be a necessity, especially when authorized by a legitimate authority The pursuit of peace must include the option of fighting to preserve it in the long-term. Such a war could not be preemptive, but defensive, to restore peace

8. Thomas Aquinas born 1225, died 1274
Thomas Aquinas was from Aquino, Italy (an Italian priest)
900 years after Augustine, he used Augustine’s arguments, but developed them into 3 conditions for a ‘just war’”
War must occur for a good and just cause/purpose (rather than for self-gain or as an exercise of power).
Just war must be waged by a properly instituted authority such as the state.
Peace must be a central motive even in the midst of violence
He also said that just war was supposed to punish “wrong-doers”

9. Just wars and ‘holy wars
Some wars are waged in the name of God, with a religious goal, they are authorsied by a religious authority and they promise the fighters a spritiual reward
These types of wars could be called ‘holy wars’
Holy wars often use ‘just war’ theory – For example, it is a ‘just cause’ to try to reclaim land for Christians which has been taken by Muslims
This reasoning was used during the West’s holy wars known as “The Crusdades” that occurred between the years of 1095 and 1291
The Crusades were Christian ‘holy wars’ that were fought for (in their view) a ‘just cause’, which was, to reclaim Jerusalem for the Christians and to defeat the infidels (the Muslims)

10. The First Crusade 1095

11. The crusades
The Crusaders were called that because they wore a red cross on their uniforms – and “crux” is the Latin word for cross, hence it turned into the word Crusades
The First Crusade was the most successful. The Third Crusade ( ) was a mixture of successes and failures for the Christians - the Muslim leader Salihhuddin defended and held Jerusalam

12. Just war and the European nation-states
A problem for Just War theory arose when Europe organised into states
The states would often be fighting each other, but both states would be Christian, both claiming to be waging a ‘just war’ in the name of God
The theory had to change: obviously it wasn’t enough to fighting in the name of God for a good cause
A new requirement emerged: serious efforts to achieve peace were necessary before turning to force

13. The Salamanca school Salamanca is in Spain
Several Spanish scholars developed the
‘just war’ theory in the 16-17th centuries
Vitoria, Suarez were among them
They said: not every wrong can justify a war
Examples of a ‘just war’ included:
In self-defense, as long as there is a reasonable possibility of success.
Preventive war against a tyrant who is about to attack.
War to punish a guilty enemy.
Even if war was ‘just’, there were limits such as protection of innocents and proportionate use of force

14. Grotius (1538-1645) was a Dutch scholar
Hugo Grotius
Grotius ( ) was a Dutch scholar
The so-called “founder of international law”
Wrote a famous book, De jure belli ac pacis, on the laws of war and peace
On just war he said it only exists:
In self-defence
For the protection of property
For the punishment of wrongs suffered by the citizens of a state

15. The peace of westphalia
Ratification of the Peace of Munster, in Munster 1648

16. Where?

17. the Peace of Westphalia: what was it?
A series of peace treaties
Signed in they ended many of the religious wars in Europe including The Thirty Years War (within the Holy Roman Empire) and The Eighty Years War (between Spain and the Dutch Republic)
The Peace of Westphalia recognised that all states are sovereign and equal
After the Peace of Westphalia, ‘just war’ theory went out of fashion: no state could clearly say whether another state had a ‘just’ cause for going to war. Each state had to respect the principle that they were all sovereign and equal
Differences would have to be resolved peacefully (in theory)
Whether the cause of war was just or not became increasingly irrelevant

18. ‘Just war’ theory became popular with the rise of Christianity
‘Just war’ summed up
‘Just war’ theory became popular with the rise of Christianity
Then it declined with the inter-Christian religious wars (when Christian states in Europe were all fighting against each other)
The rise of nation-states and the doctrine of sovereignty meant it became irrelevant
In later years, it came back into fashion again

19. Main elements of Just war theory
Today, there could be said to be 6 conditions for a war to be considered ‘just’ (although scholars differ):
The war must be for a just cause.
The war must be lawfully declared by a lawful authority.
The intention behind the war must be good.
All other ways of resolving the problem should have been tried first.
There must be a reasonable chance of success.
The means used must be in proportion to the end that the war seeks to achieve.

20. More info
Here is a good website if you want to learn more about Just War:

21. The League of Nations
The League of Nations was set up after World War I ( ) What was it? The first permanent international organisation whose goal was to maintain world peace The League was an attempt by world powers to stop another terrible conflict, like WWI It’s charter (founding document) was called The Covenant of the League of Nations Mainly drafted by US President Woodrow Wilson (came from his Fourteen Points, introduced at the Paris Peace Conference) It came into effect on 10 January Click here to read The Covenant: The Covenant said that members should submit disputes to arbitration (Article 12) Member states couldn’t resort to war until 3 months after the arbitration decision This was supposed to be a ‘cooling-off’ period for states, to reduce the chance of going to war

22. What became of the League of Nations?
It failed to prevent major conflict
In the 1930s, many major powers withdrew (Germany, Italy, Spain, Japan)
The US never joined the League of Nations (even though President Woodrow Wilson was behind the drafting of the Covenant)
The USSR was expelled in 1939
The League didn’t actually prohibit the use of force: it just tried to limit its use
The League ultimately failed: World War II began in 1939, bringing the League to an end

23. The Kellogg-Briand Pact 1928
Remember, the League didn’t prohibit the use of force
Another treaty went further & condemned the resort to the use of force: the Kellogg-Briand Pact 1928 (a.k.a The General Treaty for the Renunciation of War)
Kellogg-Brand Pact came into force on 24 July 1929
The Kellogg-Briand Pact (which is still technically in force today) stated that war can no longer be used as in instrument of foreign policy
This is now a valid principle of international law
Named after the authors (US Sec of State Kellogg, French Foreign Minister Briand)
Many states made a reservation to the treaty, reserving the right to use force in self-defence

24. World War II
The League of Nations ultimately failed
World War II broke out in 1939 and it lasted until 1945
WWII was the deadliest war in human history
Approximately 60 million people were killed - around 2.5% of the world’s population
In the wake of WWII, the United Nations was established
Its founding document is the UN Charter

25. UN Charter
The UN Charter has a preamble (ie an introduction) and 19 chapters
The preamble sets out the purposes of the UN:
“We the peoples of the United Nations determined: to save succeeding generations from the scourge of war, which twice in our lifetime has brought untold sorrow to mankind, and to reaffirm faith in fundamental human rights, in the dignity and worth of the human person, in the equal rights of men and women and of nations large and small, and to establish conditions under which justice and respect for the obligations arising from treaties and other sources of international law can be maintained, and to promote social progress and better standards of life in larger freedom… have agreed to the present Charter of the United Nations and do hereby establish an international organization to be known as the United Nations."

26. Article 1 The Purposes of the United Nations are:
To maintain international peace and security to take effective collective measures for the prevention and removal of threats to the peace, and for the suppression of acts of aggression or other breaches of the peace, and to bring about by peaceful means, and in conformity with the principles of justice and international law, adjustment or settlement of international disputes or situations which might lead to a breach of the peace …

27. Article 2
Article 2
The Organization and its Members, in pursuit of the Purposes stated in Article 1, shall act in accordance with the following Principles:
The Organization is based on the principle of the sovereign equality of all its Members.
All Members, in order to ensure to all of them the rights and benefits resulting from membership, shall fulfill in good faith the obligations assumed by them in accordance with the present Charter.
All Members shall settle their international disputes by peaceful means in such a manner that international peace and security, and justice, are not endangered.
All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.

28. Article 2(4)
All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.

29. Article 2(4)
This is part of the UN Charter BUT it is also now accepted as a principle of customary international law
It is binding upon all states in the world community
It draws upon the League of Nations Covenant
We will look at this in a separate slideshow