International Law Before and During War Part I

International Law Before and During War Part I

The last few decades have been marked by armed conflicts in which international law and international law dilemmas have come into focus. International law provides a general ban on the use of force. By force we mean in this context the physical use of military means of force – and ultimately war. At the same time, there are a large number of rules that aim to regulate the situation if war breaks out.

  • When is military use of force in line with international law?
  • Who decides what is legal use of force?
  • Is it free in war situations?
  • How do new, non-state actors challenge international law?


In the 18th and 19th centuries, the general view was that states had the right to resort to war as a means of resolving conflicts. This right was seen as one of the fundamental rights of states , and it was justified on the grounds that all states are sovereign in their own territory – within their own borders. The principle of the sovereignty of states in their own territory implies a starting point that a state is not subject to any will other than its own. But another side of the principle of state sovereignty is the prohibition against interfering in (intervening) in the internal affairs of another state . It is a basic rule of international law that states are obliged to respect the existence of other states and their choice of political, economic and social system.

It was only after the First World War – with all the suffering this entailed – that a broad agreement arose to limit the states’ right to go to war. This led to several attempts to regulate the use of force between states. The first more general ban on war is found in the so-called Briand-Kellogg Pact of 1928. After World War II followed the creation of the UN, which was to secure future generations against war, but also protect international human rights .

Article 2 (4) of the UN Charter (see facts) prohibits not only the use of war , but any use of military force. In addition, the provision prohibits states from making threats of use of force. This means that if the use of force is in itself illegal, it is also forbidden to threaten it. However, the UN Charter allows for the use of force in two cases:

  • in self-defense and
  • by decision of the Security Council .

In addition, a state can ask for help from other states to quell internal unrest.

3: The right to self-defense

The right to self-defense is enshrined in Article 51 of the UN Charter . The core of self-defense law is that a state can defend itself against a military attack from another state. At the same time, states that have not themselves been attacked have the opportunity to take up arms to defend another state. This is called collective self-defense . According to, NATO is an example of an alliance that practices collective self-defense. Pursuant to Article 5 of the NATO Charter, member states undertake to assist in armed attacks against one of the other member states. This happened for the first time after the terrorist attacks on the United States on September 11, 2001 .

The right to self-defense applies only when a state is subjected to an armed attack. From a purely evidential point of view, there can sometimes be doubts about which state is attacking. Questions can also be asked about how extensive a military action must be before it can be characterized as an armed attack. We can probably assume that the lower limit is low. An attack on a military aircraft or a naval vessel may in principle be sufficient.

The attacks on the United States in 2001 were carried out by a terrorist organization, not by a state . However, the right to self-defense does not require that the attack come from another state. There can be difficult boundaries here, and it is important to be aware of the dangers of abusing the right to self-defense . It is to extend the right to self-defense too far if military force is used against states that are not host states for terrorist bases, but which have or are suspected of having a connection to international terrorism.

It is important that we not only think about the opportunities that exist to exercise the right to self-defense against international terrorism, but also about the dangers and limitations of exercising it. For example, the United States has been criticized for violating international law by its use of unmanned drones (HHD 12-2013) against suspected terrorists in the territory of other states. The right to self-defense thus does not apply without restrictions:

  • Exercise of the right of self-defense must follow directly in response to the armed attack. The right to self-defense does not apply if a state wishes to carry out a military action long after the attack has been carried out.
  • The self-defense action shall be limited to what is necessary to repel the previous attack. But in practice, the right of self-defense is also invoked to justify military actions that have the clear character of punitive actions or actions to prevent future attacks.

4: Only by decision of the Security Council

The UN Charter gives the Security Council overall responsibility for international peace and security. If international peace is threatened, the Security Council may, in accordance with Chapter VII of the UN Charter, adopt measures to preserve or restore peace. Coercive measures can span a range from economic sanctions to the use of military force. Such decisions are binding on UN member states.

The Security Council has adopted decisions on the use of military force on several occasions, such as when Iraq invaded Kuwait in 1990. However, the Security Council’s authority is not limited to cases where an attack has already taken place. The use of military force can also be adopted where the Security Council believes that there is a threat to international peace . A broad interpretation has been used in recent years, which includes measures against terrorism and extensive human rights abuses.

Responsibility for protecting human rights is reaffirmed in the principle of ” Responsibility to Protect ” (R2P), which was adopted at the UN General Assembly Summit in 2005. The principle refers to the states’ main responsibility for protecting their population . But if abuse occurs, the Security Council can use its authority to take military action. This principle provided the basis for the Security Council’s approval of the NATO bombing of Libya in 2011 to protect against Muammar al – Gaddafi’s abuses.

Disagreement may arise over the interpretation of the Security Council’s decision. In the US- led invasion of Iraq in 2003 , the United States and other states relied on Security Council resolutions adopted in connection with the Iraq invasion of Kuwait (1990–1991). However, many argued that these resolutions could not be used for many years afterwards . In 2003, it was not a question of repelling an attack, but of enforcing the Security Council’s decision to destroy Iraq’s weapons of mass destruction. The US invasion was thus in violation of international law, they believe.

It is often highlighted as a problem that the members of the Security Council are not always able to agree on taking the necessary measures. This is because each of the five permanent member states can stop a proposal for a decision by vetoing it . The Security Council’s permanent members are the United States, the United Kingdom, France, Russia and China. The right of veto meant that the Security Council was in many ways paralyzed during the Cold War. Today, the situation is better, but there are still many who believe that the permanent members’ right of veto hinders the Security Council’s work. This can lead to states taking matters into their own hands, and using military force – even in cases where this represents a violation of international law. And even if the Security Council gives its consent, there is no guarantee for an invasion to lead to a better development. The Libyan operation (HHD 2012) admittedly removed Gaddafi, but the country is ravaged in return for civil war.

The International Criminal Court is based in The Hague, the Netherlands