Modern World Wars, or large-scale conflicts that occurred in the 20th and 21st centuries, had a significant impact on the global economy. One of the biggest impacts is changes in international trade patterns. During and after conflict, many countries experience restrictions in trade activities. For example, World War II created an urgent need to shift industrial production to military production. This not only changes the supply chain, but also affects trade relations between countries. Post-war crises often result in the need for economic reconstruction. For example, the Marshall Plan by the United States enacted after WWII provided substantial financial assistance to European countries to help them recover from the devastation. This assistance not only accelerates economic recovery, but also supports the formation of sustainable political and economic alliances, such as the European Union. War also often accelerates technological innovation. The discovery and development of new technologies in the military sector often shifts to the civilian sector post-conflict. Communications, transportation, and even space technology experienced a surge in progress thanks to military needs. For example, the development of the internet came from military projects that created stronger communications networks. Global financial relations have also been affected by modern war. Wars lead countries into debt to finance military operations, creating an increase in national debt. This changes the fiscal and monetary policies of various countries. When debt increases, countries must consider introducing new taxes or cutting government spending, which has a direct impact on the domestic economy. War also creates lasting social impacts, such as refugees. Major conflicts often result in mass migration, in which millions of people are forced to leave their homelands. This changes labor market dynamics in destination countries, often creating economic resilience or social tensions. In the short term, migrant workers can help fill gaps in the labor market, but in the long term, this requires effective integration policies. The political stability produced by post-conflict also has economic implications. Countries transitioning to democracy often face uncertainty that affects foreign investment. Investors tend to be wary of countries that appear unstable, thereby affecting capital flows and infrastructure development. The overall economic impact of the Modern World Wars shows that large-scale conflict not only changes the social and political order of a country, but also has much broader implications that impact the global economy. The adjustments that countries make to face these challenges shape patterns and policies that are relevant in a changing world.