Do international alliances always make the world safer, or can they sometimes lead to more tension?

In March 2026, the United States and Israel attacked Iran from U.S. military bases in the Middle East. As a result, Iran attacked countries across that region. Now, U.S. allies are complaining because they weren’t warned. In the following part, I will explain why I think that international alliances can sometimes lead to more tension.

My first reason is that alliances can create suspicion and increase rivalry. If many countries are in a strong alliance, other alliances might feel threatened, which can divide the world into competing groups where each see the others as a threat. An example for this is the Cold War. During the Cold War, two strong alliances were formed: NATO and the Warsaw Pact. Because both sides had very dangerous weapons, they felt threatened by the other, so they were always prepared for an attack. They might’ve never attacked each other directly, but they were still competing.

As I mentioned before, countries in the Middle East are being attacked even though it’s actually the United States and Israel attacking Iran. This brings me to my next point. International alliances can make small conflicts into larger wars. When a country is being attacked, its allies have to help. This sucks other countries into the conflict and can lead to wars. For instance, when Austria-Hungary attacked Serbia in 1914. Russia supported Serbia and Germany supported Austria-Hungary and soon countries of the Triple Entente and the Triple Alliance, which already existed before the war, were involved.

My final reason is that countries in an alliance can sometimes not agree to support the other. When that happens, there’s tension inside the alliance. For example, Spain not agreeing to helping the U.S. by not letting it use bases to attack Iran. Donald Trump then threatened to end trade with Spain to which Friedrich Merz, the chancellor of Germany, told him that he could not have a trade agreement with Europe but not with Spain.

Someone who disagrees might think that international alliances make the world safer because countries wouldn’t dare to attack a another country knowing that others support it. However, I think they are wrong because international alliances can make conflicts more complicated by involving other countries or even being the reason for the start of wars.

In conclusion, considering these points, I tink that international alliances can sometimes lead to more tension.