Based in Iraq and Syria, the Islamic State is using its chameleon-like branding and financial incentives to attract extremist groups from Egypt's Sinai Peninsula to Libya's Mediterranean coast.
When the Islamic State seized the town of Zumar, the Kurds fled. Now Kurdish fighters have taken control, and it's the Arabs who have been driven out. Is this the future of Iraq?
The new personnel will serve "in a non-combat role to train, advise, and assist Iraqi Security Forces, including Kurdish forces," White House press secretary Josh Earnest says.
Until August, 24-year-old Aza Betwata was in Holland, enjoying beef and cabbage and studying to be a social worker. Now, he's among the hundreds of exiled Kurds who have returned and taken up arms.
A checkpoint near Kirkuk marks the line between Kurdish-controlled territory and the world of Islamic State extremists. Some 5,000 civilians stream across daily, lives and families divided.
Thousands of international recruits have crossed into Syria from Turkey to join the Islamic State. A Syrian man who helped smuggle those jihadis in explains how it worked, but says he's stopped now.
Iran's President Hassan Rouhani told the U.N. that the solution to the problem of ISIS now must involve the region. He also said resolving the Iran nuclear issue could lead to greater cooperation.
Signaling a broadening of the American offensive to date, the president said he would not hesitate to order strikes inside Syria. "If you threaten America, you will find no safe haven," Obama warned.