Many people think World War 3 will happen, but I believe the chances are low. Why did World War 1 and World War 2 happen? World War 1 and World War 2 happened partly because of mutual defense alliances countries had agreements that if one was attacked, others would join the war to support them. This helped escalate local conflicts into global wars. For example, in World War 1, when one country was attacked, its allies entered the war too. In World War 2, many countries were again drawn in because of those alliances and retaliations. In contrast, in recent conflicts like when the USA and Israel attacked Iran, no major ally such as Russia or China has openly entered the fighting to defend Iran. This suggests that we don’t currently have the kind of alliance system that would easily pull multiple major powers into a global war. So right now, although there are serious regional conflicts and global tensions, the situation isn’t structured in the same way as it was before World War 1 and 2, which makes a full-scale World War 3 less likely (This is my though but not impossible).