1. Looking at the new challenges facing international law from the Iraq War Abstract: Without the authorization of the UN Security Council, the United States bypassed the UN Security Council and launched a war to overthrow Saddam Hussein's regime in Iraq, which undermined the foundation of international law. Many American military technologies made their debut and were used in this war. In this context, the article aims to briefly introduce the law of war and armed conflict in international law, the historical evolution of international law against war and the new problems faced by international law. Keywords: Iraq; War; International law ii. What did the United States get from the Iraq war? Global forces against regional forces, the economic interests behind the war, and the impact of the Iraq war on the American economy and even the world economy 3. The return of the Iraq war and geopolitics. Before and after the Iraq war, one of the most used categories in international media, international academic circles and critics was "geopolitics". In the past ten years since the end of the Cold War, we can find that there have been two upsurge in the use of geopolitics: the first time was after the drastic changes in Eastern Europe and the disintegration of the Soviet Union in the late 1980s, 199 1, which was generally regarded by international media and academic critics as a truly great geopolitical change; This Iraq war is the second time. Why did the "geopolitics" craze resurface against the background of the second Iraq war in the spring of 2003? To what extent did the Iraq war cause great changes in the geopolitical pattern? What are the motives and characteristics of this geopolitical change? How will it affect the future trend of the international community?