During the battle for Kobane many people were willing to join the Kurdish YPG forces to aid in battle against ISIS.  Catherine Herridge interviewed on such American…. 
(Via Fox News) All it took was a plane ticket, and an informal background check over Facebook. Then he was ushered to the front lines in Syria, fighting against the Islamic State.
In a rare, exclusive interview with Fox News, a U.S. military veteran with multiple tours in Iraq detailed his journey to Syria to fight against ISIS, on the condition his identity was protected.
The veteran, who asked to be identified as “John,” described a surprisingly simple process that took him from America to the dangerous Syrian civil war – and not as part of the U.S. military.
“I just went online and bought a ticket. It was that easy. It was like booking a flight to Miami Beach,” said “John.”
Then he found a Kurdish group known as the YPG.
“There was a Facebook page for it — shot them a message, expressed my interest, they got back to me, told me to send them, essentially, a resume for their vetting purposes,” John explained.
His military service was also a bonus.
“What I believe is that they are European go-betweens, they are not in Kurdistan, they operate receiving information of interested Westerners, and then they either relay it or make a decision themselves of whether or not this person is suitable to work with the YPG,” he said. “They sent (a) message saying I was approved and someone would be waiting on me.”
John was met at the airport in Iraq. And almost immediately, they drove him to the front lines.  (read more)