Jim McMahon

For this boy and millions of other Iraqi children, everyday life is anything but normal. The boy pictured here in Mosul, Iraq, is biking past an oil field set ablaze in October by the terrorist group ISIS. Aiming to create a strict Islamic state, ISIS has seized large swaths of territory in Iraq and Syria, killed thousands of people—including hundreds of Westerners—and currently keeps about 3,500 women and children as slaves. In October, with U.S. military support, Iraqi forces began to retake Mosul, Iraq’s second-largest city and an ISIS stronghold.

The U.S. has also conducted air strikes against ISIS fighters in Syria. Combating ISIS will be one of President-elect Donald Trump’s most pressing challenges when he takes office this month (see "How Trump Could Change America"). Experts say young people are among the terrorist group’s most vulnerable victims. “The children under ISIS have lost three years,” says Anthony Cordesman of the Center for Strategic and International Studies in Washington, D.C., “and [they] will pay the cost in development for years to come.”