Why do people start wars even though it hurts their country too – and they might lose?

Grace, 9, Belfast

Before governments, countries and writing, there was war. People have always fought with each other. Archaeologists have discovered skeletons with weapon injuries that are over 10,000 years old.

Wars are very serious because they hurt people and the environment. They happen for many different reasons, and each war is different. People who start wars often think that the short-term benefits of a war are worth the harm to their own people. But they don’t always understand the long-term consequences of their actions.

Experts use something called the “just war theory” to understand whether it’s ever OK to fight a war. This is a very old, but useful, set of ideas that help people decide if a war is fair, how soldiers should behave and how to protect people who are not fighting, like children and families.

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Just war theory says that countries have a right to defend themselves from invasion when another country attacks them. However, it also says that the harm from war must not be worse than the problem, that someone must actually be able to win and that people should try talking, negotiating and making agreements before they fight.

It provides rules for countries at war to follow. The rules say that normal people and the things that they need, such as hospitals, power plants and schools, should never be attacked because they help everyone live safely.

These ancient ideas have become part of the modern international laws and agreements that help make our world more peaceful. Unfortunately, not all countries follow just war theory when they go to war. Thankfully, we have laws in place to punish the leaders or soldiers who break the rules.

Why do wars start?

Wars can start due to a disagreement, fear or a desire for more power. Unfortunately, some leaders will choose war because they don’t want to appear weak. Or they might go to war to distract their own people and stay in control, because they feel vulnerable and unpopular. They might make a bad decision, really believe that they are right, then underestimate how long the war will last. The best leaders do not start wars in this way, do not make these mistakes and care about their people’s long-term wellbeing.

Another reason why people start wars is because they think that invading another country will make them stronger or richer. As we use up things we cannot easily replace, such as fossil fuels for our cars and rare metals for our phones and computers, this increases competition between countries to own the remaining resources.

Peace experts like me also explain that climate change contributes to wars, as it makes it harder for people to access good water and farmland. It is so much better for everyone when countries bargain with each other and share resources, instead of starting wars.

Even though wars are happening now in countries like Ukraine, Afghanistan and Iran, most countries still solve their problems peacefully by talking and working together.

Many experts think that wars are evidence of failure, and that everyone loses when they fight instead of working together to create agreements and compromises. Pacifists believe that war is always wrong and that we must strive to find peaceful solutions. I think that they have the right idea, and that a more peaceful world is definitely possible.