After the 9/11 terrorist attacks on the US, the world has witnessed some dramatic changes in governments’ policies combating terrorism. The US government took the lead in these changes which has concerned international lawyers all over the world. In fact, the US government treated its prisoners inhumanely and their most fundamental rights have been denied as the government argued that the Geneva Conventions neither apply to its declared war on international terrorism, nor to the prisoners captured in this war. That means, the detainees in Guantanamo Bay and elsewhere could be held forever without any trial or charges. This book has challenged the US government’s arguments and has found that there have been grave breaches of the Geneva Convections, and some war crimes and crimes against humanity have been committed by the US government.