Casus belli facts for kids

A casus belli (say "KAH-soos BELL-eye") is a Latin phrase. It means an event or situation that directly causes a country to start a war. Think of it as the official reason or spark that makes a war begin. Sometimes, a country might even try to provoke another country. This is done to create a reason to legally start a war, often claiming self-defense.

What is a Casus Belli?

A casus belli is like the final straw before a conflict breaks out. It's the specific action or event that a country points to as its justification for going to war. Without a clear casus belli, starting a war can be seen as an act of aggression.

Why is a Casus Belli Important?

In international law, countries are generally not allowed to attack other countries without a good reason. A casus belli provides that reason. It helps a country explain its actions to the world. It can also help gather support from its own people and allies.

Famous Examples of Casus Belli

The Arrow Incident (Second Opium War)

One example is the Arrow incident in 1856. This event helped start the Second Opium War between Britain and China. A Chinese-owned ship called the Arrow, which was registered in Hong Kong (a British colony at the time), was boarded by Chinese officials. They arrested the crew, claiming piracy. Britain saw this as an insult to its flag and a violation of its rights. This incident became a key reason for Britain to declare war on China.

The Maine Incident (Spanish-American War)

Another famous casus belli was the sinking of the USS Maine. This American battleship exploded in Havana Harbor, Cuba, in 1898. More than 260 American sailors died. At the time, Cuba was under Spanish rule, and there was a rebellion happening. Even though the cause of the explosion was unclear, many Americans blamed Spain. The cry "Remember the Maine!" became a rallying call. This event directly led the United States to declare war on Spain. As a result, the U.S. gained control of Cuba and the Philippines.

The Iraq War (Weapons of Mass Destruction)

In 2003, the Iraq War began. The United States and its allies stated their main reason was that Saddam Hussein, Iraq's leader, had weapons of mass destruction (WMDs). These were said to be dangerous chemical or biological weapons. The U.S. presented this as the casus belli. However, years after the war started, no WMDs were found in Iraq. This showed that the stated reason for war was not true.

Assassination of Archduke Franz Ferdinand (World War I)

Perhaps one of the most well-known examples is the Assassination of Archduke Franz Ferdinand of Austria. He was the heir to the Austro-Hungarian throne. In 1914, he was assassinated in Sarajevo. This act was the direct spark that ignited World War I. Austria-Hungary blamed Serbia for the assassination. They issued a list of demands to Serbia. When Serbia did not fully agree, Austria-Hungary declared war. This quickly led to a chain reaction of alliances, pulling many countries into the devastating war.

Images for kids

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  Cartoon of belligerent Uncle Sam placing Spain on notice, c. 1898

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  Alfred Naujocks, who organized and led the Gleiwitz incident on the orders of Heydrich.

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  February 5, 2003 – U.S. Secretary of State Colin Powell holding a model vial of anthrax while giving the presentation to the UN Security Council.

See also

In Spanish: Casus belli para niños