Modern World War, a term that includes conflicts that occurred in the 20th and 21st centuries, has had a significant impact on global geopolitics. When discussing its impact, it is important to review how the war shaped relations between countries, influenced foreign policy, and created new strategic alliances. One of the most striking impacts is the emergence of large countries as dominant powers. For example, after World War II, the United States and the Soviet Union emerged as competing superpowers, sparking the Cold War. This tension led to the formation of ideological blocs: capitalism led by the US and communism championed by the Soviet Union, which had a major influence on the policies of countries around the world. In addition, the Cold War created influence in regions such as Southeast Asia and the Middle East. Countries like Vietnam and Korea were caught in civil wars with the intervention of great powers seeking to spread their ideologies. These conflicts changed the geopolitical map, creating new allies and enemies and harming many civilians. In the modern era, terrorism has become a global threat that offers new challenges to international security. The attacks of September 11, 2001 changed the focus of US and allied foreign policy, prompting the invasions of Afghanistan and Iraq. In this context, many countries are experiencing an identity crisis, where they have to choose between national security and human rights. The war on terror has also accelerated a shift in power to countries outside the west, such as China, which has exploited the instability to expand its influence in Asia and Africa. Cyber warfare and disinformation tactics are now becoming new tools in modern conflict, changing the way countries interact. Cyber attacks can weaken critical infrastructure without the need for military intervention. A clear example of this includes the attack on energy facilities in Ukraine by Russia, which raised cybersecurity concerns in other countries. The climate crisis facing the world is also an important factor in modern geopolitics. Resource-rich countries, such as those in the Middle East, need to adjust policies in the wake of increasing demand for renewable energy. Instability due to climate change has the potential to cause mass migration, adding complexity to relations between countries. Initiatives such as the Belt and Road under China’s leadership show the economic impact of new conflicts and alliances. Countries are competing to build infrastructure and strengthen trade relations with other countries. China’s growing influence awaits challenges from western countries seeking to maintain control over global trade and technology. In conclusion, the Modern World War has influenced all aspects of global geopolitics. From the power vacuums resulting from conflict, to the emergence of new ideologies, to shifts in military strategy and cybersecurity, war continues to be a key driver in shaping the future of international relations. Countries must constantly adapt and find ways to collaborate in facing modern-day challenges, in order to create greater stability on the world stage.