While the United States comprises only 5% of the world’s population, it holds 25% of the world’s prisoners within its borders. According to the American Civil Liberties Union, the US prison population has risen an incredible 700%, rendering the country the world’s largest jailer. At present, one in every 99 adults in the US is locked up — the highest rate of imprisonment in US history. What’s primarily at root? The failed “War on Drugs” and mandatory minimum sentences.