Explain how international law is made, why states obey it, and how it is enforced.

What this dot point is asking

This dot point asks you to explain three linked things: how international law comes into existence, why states actually follow it, and how it can be enforced when they do not.

How international law is made

There is no world parliament, so international law is created by states themselves in two main ways:

• By treaty: states negotiate and sign a treaty, then ratify it through their own domestic process. A treaty binds only the states that agree to it. Multilateral treaties such as the United Nations Charter are negotiated through international organisations and conferences.
• By custom: where states consistently behave in a certain way over time, believing they are legally obliged to (opinio juris), that practice can harden into binding customary international law that applies even to states that never signed a treaty.

Why states obey international law

Despite the lack of a world police force, states comply with international law most of the time. Reasons include:

• Consent: states are usually bound only by rules they have agreed to, so obligations reflect their own interests.
• Reciprocity: a state that breaks the rules cannot expect others to keep them, so mutual benefit encourages compliance, for example in trade and diplomacy.
• Reputation: states that breach their commitments lose trust, allies and influence.
• Pacta sunt servanda: the customary principle that agreements must be kept, which underpins the binding force of treaties.
• Order and stability: predictable rules benefit all states by reducing conflict and supporting commerce.

How international law is enforced

Enforcement is the weakest part of international law, because there is no central authority that can compel a sovereign state. The available mechanisms include:

• The United Nations: the Security Council can authorise measures, including economic sanctions or, in extreme cases, military action, although its permanent members can veto action.
• Sanctions: states or groups of states impose trade or financial restrictions to pressure a state into compliance.
• International courts and tribunals: the International Court of Justice resolves disputes between states that consent to its jurisdiction, and the International Criminal Court can prosecute individuals for serious crimes such as genocide.
• Diplomatic pressure: negotiation, condemnation and the withdrawal of recognition or cooperation.

These tools are uneven. They tend to work against weaker states and struggle to constrain powerful ones, especially the permanent members of the Security Council.

For exam answers, separate the three parts clearly: how the law is made (treaty and custom), why it is obeyed (consent, reciprocity, reputation, order), and how it is enforced (United Nations, sanctions, courts, diplomacy), noting that enforcement is the system's main weakness.