Westerners join Kurds fighting Islamic State group(ISIS) in Iraq.

In this photo, Jordan Matson, 28, right, a former U.S. Army soldier from Sturtevant, Wis., takes a break with other fighters from the main Kurdish militia, the People's Protection Units, or YPG, in Sinjar, Iraq. Matson and dozens of other Westerners now fight with the Kurds, spurred on by Kurdish social media campaigners and a sense of duty many feel after Iraq, the target of a decade-long U.S.-led military campaign, collapsed under an Islamic State group offensive within days last summer.