Too often states have faced internal threats from violent non-state actors seeking to overthrow the government and replace it with their own. Too often have states’ efforts fallen short in overcoming such an internal menace. This begs the question: is successful counterinsurgency possible? This question took the centre stage in light of the United States’ involvement in Afghanistan (2001) and Iraq (2003). Quickly it became evident that superior military strength did not translate into military success. The American way of war could not mitigate the escalating situation on the ground. The descent into chaos in Iraq has perpetuated the need for a new approach to counter the insurgents. This approach came to be known as “population-centric” counterinsurgency. By 2006, it appeared in the form of the US Army/Marine Corps joint publication entitled Field Manual 3-24 Counterinsurgency. The new manual offered an arguably new way of addressing insurgencies, shifting the focus from the enemy to the key population. For the US Army and Marine Corps, this ‘new’ thinking presented a radical departure from previous practices. However, was the initial success in Iraq, indeed, indebted to the implementation of the manual? And how ‘new’ was this new approach the manual laid out? In this book, the author closely examines the situation in Iraq and assesses in how far the new manual could be said to have contributed to the reduction of violence in Iraq in 2007. In addition, the core elements are examined in detail and contrasted with previous manuals in order to highlight that the ‘new’ thinking might not have been that new after all.