International Law vs. National Law: Why Do We Need Both?

By Dr. James Barney  |  04/08/2025

Let us assume that two warring nations use a private company’s drones in conflict between themselves. What law would apply in assessing the possible liability of the private company if the use of drones created for a civilian purpose, but modified by the belligerents, results in the death of civilians or damage to infrastructure in one of the countries?

This types of situations have arisen in the conflict between Ukraine and Russia. They raise questions about the often-murky divide between international and national law. Determining who has the ability and power to hear such disputes – and enforce any broken laws or treaties – also becomes a challenge.

National law helps maintain national legal order within a particular nation-state, and international law governs parties’ activities on a global scale. Each nation has the power to define its international obligations. Additionally, each state can create internal laws that hinder the enforcement of international law.

International and national laws each have far-reaching impacts. They affect everything from foreign relations to trade and the preservation of human rights. Understanding these consequences requires us first to recognize the boundaries between national and international law – and where the lines blur.

What Is National Law?

National law is a type of domestic law that exists to maintain national legal order. Essentially, it governs the civil and political rights of a country’s people.

The United Nations Educational, Scientific, and Cultural Organization (UNESCO) defines “national law” as a “binding rule or body of rules prescribed by the government of a sovereign state that holds force throughout the regions and territories within the government’s dominion.”

In the U.S. legal system, our federal law serves as “national law.” It governs every person, institution, and entity, as the Administrative Office of the U.S. Courts states.

How Do Domestic Courts Uphold National Law in the US?

Because the U.S. has a complex system of federalism, our national legal system includes state and federal courts. Federal courts hear federal cases involving national law. However, state courts also hear cases pertaining to national law.

“State courts play a significant and independent – though often underappreciated – role in the implementation of federal programs and policies,” the National Center for State Courts (NCSC) reports.

State and federal courts frequently possess overlapping authority to hear certain types of cases. Consequently, there are disparities between state and federal law, most notably in environmental regulation, immigration, and employment law.

Nonetheless, our domestic court system relies heavily on federal courts to hear cases involving national law. According to the United States Courts, such cases may revolve around:

• The constitutionality of the law
• U.S. laws and treaties
• Conflicts involving ambassadors and public ministers
• Disputes between multiple states
• Admiralty law
• Bankruptcy
• Habeas corpus (the legality of an incarceration)

What Is International Law, and Who Creates It?

Law is an agreed-upon set of rules that govern behavior between various parties. The rules that define international law draw from international treaties, customs, practices, and individual nations’ laws. These rules govern the relationships between various actors.

The current international law regime was established alongside the development of the modern nation-state. As a result, international law is often the agreement of nations regarding their behavior.

In the modern era, organizations like the United Nations (U.N.) and its International Law Commission develop international laws. Other organizations also contribute to the international lawmaking process:

• The World Trade Organization (WTO) handles trade disputes.
• The International Maritime Organization (IMO) regulates shipping.
• The International Telecommunication Union (ITU) sets global standards for cybersecurity and AI governance.

These organizations set frameworks, but enforcement depends on political and economic leverage. It is not uncommon for a country to ignore a trade ruling by the WTO or to refuse an arrest warrant by the International Criminal Court (ICC), as evidenced by recent events. 

What Does International Law Address?

As the United Nations Information Service (UNIS) Vienna states, international law recognizes “a wide range of issues of international concern.” The organization specifies some of these issues:

• Human rights
• Disarmament
• International crime
• Refugees
• Migration
• Problems of nationality
• The treatment of prisoners
• The conduct of war
• The environment
• International waters
• Outer space
• Global communications
• World trade

What Systems Are in Place to Uphold International Law?

Jurisdiction depends on the type of case and the willingness of nations to cooperate. There are numerous enforcement mechanisms.

One prominent example is the International Criminal Court. The ICC is a body composed of more than a hundred signatories that prosecutes individuals for war crimes, genocide, and crimes against humanity.

As recent history has revealed, the ICC and other enforcement mechanisms are not sufficient in many cases. Powerful countries in the international order can simply opt to not cooperate.

For example, the conflicts in Gaza and Ukraine have sparked high-profile allegations of war crimes and genocide. Both situations have been the subject of a great deal of press and controversy. Cases surrounding each conflict have been filed in the ICC. Still, offending parties continue to evade justice.

Like the ICC, the International Court of Justice ( ICJ) also helps to uphold international law and settles disputes between states. Its rulings often deal with border conflicts or allegations of treaty violations.

Article 38 of the Statute of the International Court of Justice states that the ICJ settles disputes by applying:

• International conventions, whether general or particular, that establish rules expressly recognized by the contesting parties
• International custom, as evidence of a general practice accepted as law
• The general principles of law recognized by civilized nations

Enforcement relies on the UN Security Council, however. Therefore, compliance with any judgment issued by the ICJ often depends upon each party’s willingness to maintain good standing in the international order. In other words, compliance depends on political motivations, rather than legal obligations.

There are additional international courts as well. One court is the International Tribunal for the Law of the Sea (ITLOS), which specializes in enforcing maritime law. The United Nations also provides other courts and tribunals that comprise the international legal system.

What Are the Shortcomings of International Legal Systems?

Major powers like the U.S., Russia, and China do not always recognize the authority of international legal systems over their nationals. In fact, international law enforcement mechanisms like the ICC have been largely ineffective at holding individuals and states accountable for allegations.

In theory, international law should provide a predictable framework for a country’s actions that take place outside its borders. Accordingly, it should address topics such as diplomacy, trade, and conflict resolution.

In practice, though, enforcement is weak, and compliance is often voluntary. The system only works as long as nations find international law beneficial. Therefore, geopolitical issues, such as competition between large and powerful countries like the United States and China, can create conflicts of interest.

The real question is not whether international law exists – it is whether nations and corporations see compliance as being in their best interest. Currently, many countries do not see compliance as necessary, which is problematic.

Suppose the law only exists in theory or is applied to some international actors and nation-states, but not all. In that case, there is a real chance that the series of norms that serves as the foundation for the international legal system may break down.

If legal frameworks fail to adapt, we risk moving toward a system governed by raw power and economic leverage rather than laws and treaties. International law works when it aligns with incentives. When it does not, though, history shows that power fills the void, and the future may look like the past, which is not very promising.

Can International and National Law Adapt to Change?

As technological advances and scientific discovery redefine our world, international and national law must also evolve to reflect new possibilities. For example, the rise and widespread adoption of AI could completely transform modern warfare.

At the same time, space exploration is a rapidly evolving, trillion-dollar industry with private companies and numerous nations in the fold. Yet, international and national law struggle to keep up with technological innovation.

The lack of comprehensive legal frames in space and AI are similar to what occurred in the Age of Discovery from 1418 to 1620, which resulted in a period of conflict. We are witnessing history repeating itself. Just as maritime law evolved alongside global trade, modern space law is shaped by corporate ambition and geopolitical competition.

Individual nation states and alliances of nation-states like the EU are scrambling to pass national and international law to deal with a host of emerging issues sparked by innovative technologies.

Time is of the essence when it comes to space exploration and AI. The challenge for international law is to regulate these high-stakes frontiers before economic and strategic interests take precedence over legal norms.

What Are the ‘Gray Areas’ of International Law?

Although international law is a robust body of law, it continues grappling with certain issues, like AI, space, cybersecurity, and global health. However, conflicts between the largest and most powerful nations prevent the development of comprehensive international law in these fields.

AI

Several nation-states and supranational organizations have already taken measures to regulate the use of AI. For example, the EU’s AI Act sets a regulatory framework, but global enforcement remains voluntary.

Consequently, many issues surrounding AI are either inadequately regulated or completely unaddressed. For example, autonomous weapons raise major legal and ethical concerns, and there is no clear accountability for AI-driven warfare. This problem may potentially become a large issue.

Space

Despite the existence of the Outer Space Treaty of 1967, space resources are still vulnerable to exploitation. The 1967 Outer Space Treaty is a Cold War relic, and there are significant gaps in the protections it provides.

The Artemis Accords aim to fill in those gaps. Countries aligned with the U.S. have agreed to the Accords, but key players like China and Russia have yet to sign. Any nations who refuse to cooperate weaken the whole endeavor and call into question the overall effectiveness of international space law.

Regarding appropriate activities in space, private companies also push boundaries. Private organizations who engage in space exploration and exploitation seek to establish norms and rules to govern the extraction of resources from the Moon. Therefore, modern space agreements must account for corporate actors as well as states.

Cybersecurity

Over the past decade, cybersecurity threats have exposed additional weaknesses in international law. The openness of the internet allows criminals, nation-states, and bad actors to engage in activities that could damage economies and harm lives.

Cybercrime persists, not because of lack of regulations, but due to lack of compliance with existing conventions. For example, the failure of key nations like Russia and China to participate in the Budapest Convention on Cybercrime limits its effectiveness.

Global Health

Despite national borders, the world is an interconnected place. On any given day, billions of goods and millions of people travel from place to place. However, the world still lacks a solid legal framework to deal with global health crises like COVID-19.

In 2020, various international organizations, like the World Health Organization’s International Health Regulations sought to coordinate a unified response. The COVID-19 pandemic, however, exposed their weaknesses. States acted in self-interest rather than following guidelines, disrupting trade and travel.

How Do Human Rights Treaties Influence International and National Law?

According to the U.N.’s Office of the High Commissioner for Human Rights (OHCHR), there are nine main international human rights treaties. They cover everything from civil and political rights to “cruel, inhuman, or degrading treatment.”

Each U.N. member has ratified at least one of these nine human rights treaties. Additionally, the U.N.’s Foundation of International Human Rights Law reports that “80 percent have ratified four or more, giving concrete expression to the universality of the UDHR and international human rights.”

Some nations incorporate international agreements into national law automatically as part of the ratification process, says the U.N.’s International Norms and Standards Relating to Disability. In other words, when these nations consent to comply with a given treaty, they simultaneously integrate that treaty’s terms into their national laws.

Nonetheless, international human rights laws establish non-negotiable requirements. “Through ratification of international human rights treaties, governments undertake to put into place domestic measures and legislation compatible with their treaty obligations and duties,” the U.N. states.

What Is the Difference Between International Law and Customary International Law?

Unlike international and national law, customary international law is not a written code.

The European Center for Constitutional and Human Rights (ECCHR) provides additional context: Customary international law is based “on consistent state practice along with states’ belief that they are acting in accordance with a binding norm.”

Interestingly, customary international law can – and, presumably, does – conflict with international law in certain instances. Still, “treaty-based international law will not necessarily override customary international law,” per the ECCHR.

Charting a Necessary Path Forward

International law provides a high degree of order and stability, but only when major countries comply. Unfortunately, the enforcement mechanisms in place are simply not strong enough to reprimand or influence the actions of powerful countries. As a result, the strongest geopolitical powers can avoid accountability if they opt to play outside of the laws and norms.

Tensions increase when powerful players in the geopolitical system question international law's central norms, as has occurred in recent years. A world without international law devolves into brutality and conflict, expressions of pure power. Each country seeks to push acceptable boundaries, conflicting with others doing the same.

To prevent the international system from devolving into chaos, nation-states and private parties must compromise and resolve to sort out their differences. Major players should meet at the bargaining table, not the battlefield, to address the ambiguities that exist within international covenants. National and internation law must also account for emerging technological fields, such as AI and cybersecurity, as well as the “rules of the road” in space.  

International order has prevented direct conflict between major geopolitical powers since World War II. Nevertheless, the lack of compromise between these powers is particularly concerning in the nuclear age.

Given the life and death consequences of direct conflict, the need for legally binding agreements in the international community is abundantly clear. Questions of international and national law, conflict resolution, and law enforcement on a global scale are not merely academic. Rather, these issues impact the lives of everyone and demand our attention, study, and discussion.

Legal Studies Degrees at American Public University

Like national law, international law is not a fixed system; it is an evolving response to crises and power shifts. The Geneva Conventions became stronger after WWII, and trade laws adapted after the 2008 financial crisis.

To help students better understand the processes through which laws change, American Public University offers several legal studies programs:

• An online Associate of Science in Legal Studies
• An online Bachelor of Science in Legal Studies
• An online Master of Arts in Legal Studies

Completing a legal studies degree can provide valuable insight into both international law and national legal systems. For more information, visit APU’s Security and Global Studies program page.