ISIS Most Powerful Terrorist Organization In The World

ISIS Most Powerful Terrorist Organization In The World
In this photo taken Saturday, June 21, 2014, militants from the al-Qaida-inspired Islamic State of Iraq and the Levant (ISIL) patrol in Fallujah, 40 miles (65 kilometers) west of Baghdad, Iraq. Sunni militants have seized another town in Iraq's western Anbar province, the fourth to fall in two days, officials said Sunday, in what is shaping up to be a major offensive in one of Iraq's most restive regions. (AP Photo)

ISIS, with an estimated $2 billion, and controlling 40,000 square miles in Iraq and Syria, has become the most powerful terrorist organization in the world. More from ABC News Crime and Terrorism Analyst Brad Garrett.