Crime of aggression

Sometimes, leaders start big wars.

This is called aggression. It is when one land uses its army to attack another.

Long ago, people thought this was very wrong. They said wars should only be for self-defense. A man named Aron Trainin had an idea. He said leaders should be held responsible for starting wars.

After a big war, leaders were put on trial.

This helped make new rules for the world. These rules help keep peace between lands. We can learn from the past to stay safe.

A crime of aggression happens when a country uses its military to attack another.

This can include invading a land or using a blockade to stop ships. This is a crime for leaders. Only people with power can plan these big attacks.

For a long time, thinkers used "just war theory." This idea says war is only okay for self-defense. A man named Aron Trainin helped change the law. He said leaders should be held responsible for starting wars.

After World War II, many leaders faced trials.

The Nuremberg trials were very important. The court called aggression the "supreme international crime." They said it holds all the evil of war. At these trials, 12 people were found guilty of crimes against peace. Other trials happened in places like China and Poland.

These trials helped create new rules for the whole world.

A crime of aggression is a very serious act. It happens when a country uses its military to attack another land. This can include invading a country or taking over its territory. It can also mean using a blockade to stop ships from reaching a port. These actions are often called crimes against peace. This crime is unique because it is a leadership crime. Only people with the power to shape a nation's policy can commit it. Ordinary soldiers who carry out orders are usually not the ones responsible.

Many people have studied why starting a war is wrong. This study is called just war theory. This idea says that war is only fair if it is for self-defense. Fighting to take more land from someone else is considered unjust. Long ago, thinkers like Hugo Grotius looked at how war affects individual rights. In the 1700s, a theorist named Emer de Vattel also wrote about these ideas. Even in 1815, leaders tried to outlaw Napoleon for disturbing the peace of the world. These early ideas helped build the foundation for modern laws.

New ideas about these crimes grew after World War I. In 1918, British Prime Minister David Lloyd George spoke about the loss of millions of young men. He argued that invading a country without its consent was an outrage. However, the United States did not agree to prosecute leaders at that time. Later, a Soviet jurist named Aron Trainin made a big proposal. He argued that while a state is responsible for war, individuals must be held responsible too. His ideas gained more attention around 1943 during World War II.

After World War II, many important trials took place. The Nuremberg trials were a major part of this history. At these trials, the court called aggression the "supreme international crime." They said it contains the "accumulated evil of the whole" because war itself is so harmful. The court looked at many different attacks. These included invasions of Poland, Denmark, Norway, and the Soviet Union. In total, 12 people were convicted of these crimes at Nuremberg. Other trials for aggression happened in places like China, Poland, and Tokyo.

Today, the crime of aggression is a core part of international law. In 2010, many countries met at the Kampala Review Conference. There, they agreed on how the International Criminal Court should handle these crimes. This helps ensure that the rules for peace are clear for everyone. Aggression is now seen alongside other major crimes like genocide and war crimes. It is a way for the world to say that peace is a rule that must be followed. By holding leaders accountable, the world tries to prevent such large-scale harm from happening again.

A crime of aggression, also called a crime against peace, is a serious violation of international law. It involves the planning, starting, or carrying out of large-scale military force against another state. This crime includes specific actions like an invasion, a military occupation, or the annexation of territory through force. It also covers the bombardment of locations and the military blockade of ports. Unlike many other crimes, aggression is considered a leadership crime. This means only those with the power to shape a nation's policy can be held responsible. Ordinary soldiers who simply carry out orders are generally not the ones charged with this specific crime.

The moral reasons for this law come from just war theory. This long-standing philosophy suggests that waging war for territorial gain is unjust. According to this theory, a war is only just if it is fought for self-defense or to help allies. Early thinkers helped shape these ideas over many centuries. Hugo Grotius, a founder of international law, believed aggression violated individual rights. In the 1700s, theorist Emer de Vattel provided a philosophical basis for these concepts. Even in 1815, Napoleon was outlawed for disturbing the peace of the world. These ideas established that aggression is a grave moral and legal wrong.

Following World War I, leaders began to discuss making aggression a legal crime. In 1918, British Prime Minister David Lloyd George spoke about the millions of young men lost in the war. He called the invasion of independent countries without consent an outrage against international law. However, the United States rejected the idea of prosecuting leaders at that time. The League of Nations was created to maintain peace, but it did not successfully criminalize aggression. While the 1928 Kellogg–Briand Pact did not name war a crime, it later served as a precedent for trials after World War II.

During World War II, new legal ideas emerged from the devastation of the conflict. Soviet jurist Aron Trainin proposed that individuals, not just states, should face criminal responsibility for aggressive wars. He argued that while a state has political responsibility, the individuals in power must be held accountable. Trainin specifically pointed to Adolf Hitler and the Nazi Party for their actions against the Soviet Union. Other thinkers like Hersch Lauterpacht and Marcel de Baer also made similar proposals. By 1944, there was growing pressure for an international tribunal to judge these acts of aggression.

The Nuremberg trials became the most famous instance of prosecuting these crimes. The International Military Tribunal ruled that aggression was the "supreme international crime." The court stated that it contained the "accumulated evil of the whole" because of the harm caused by war. The prosecution showed that Nazi leaders had a premeditated conspiracy to disrupt the European order. They traced this planning back to Hitler's book, *Mein Kampf*, and several secret meetings held between 1937 and 1939. The court looked at many specific acts, including the invasions of Poland, Denmark, Norway, and the Soviet Union. In the end, 12 of the 22 defendants were convicted of these crimes.

Other nations also held trials for aggression during this period. In Finland, a tribunal was established to try those who contributed to the country's involvement in war between 1941 and 1944. Eight men, including the wartime president Risto Ryti, were tried. Initially, seven were convicted, but the judgment was later revised to convict all eight defendants. These individuals faced penalties of up to ten years of imprisonment with hard labor. Other major trials for aggression took place in China, Poland, and Tokyo. These cases helped establish how international law could address the actions of leaders.

Today, the crime of aggression is a core part of international criminal law. It is treated with the same seriousness as genocide, war crimes, and crimes against humanity. In 2010, at the Kampala Review Conference, states parties to the International Criminal Court adopted new definitions. These rules explain how the court can exercise jurisdiction over the crime. While the definition can sometimes be vague, such as in discussions regarding a "war on terror," the crime is generally accepted in international customary law. Some countries also use their own national laws to prosecute aggression through universal jurisdiction.