Over the last 20 years, efforts to stabilize Iraq have been plagued by two powerful terrorist groups: al-Qaida in Iraq and then its progeny, the Islamic State (ISIS). While the country has fortunately managed to hold together in that time, there is still a long way to go toward security and stability in Iraq. Lt. Gen. Michael Nagata, the former director of strategy at the National Counterterrorism Center, discusses his time fighting extremist threats in Iraq, why the battle against ISIS is far from over and what the country needs to achieve peace.