Racism has existed throughout human history. It has caused wars, slavery, the creation of nations, and laws. However, racism has never been the "only" cause of wars and slavery. Leaders often used racism to make their actions seem all right. For example, the Nazis used the idea that Slavic peoples were less than human to make it seem all right to take over those people's countries. In the United States, white people used the idea that African Americans were less than them to make it seem all right to treat them as property.