How evil and how determined is ISIS?

For how evil they are, consult the Yazidi women who have escaped enslavement.

"Every time a woman escapes we learn more about how they are using Yazidi women," he said. 

Domle said the women, especially those who end up in ISIS strongholds in Syria, tend to be traded or sold three or four times as fighters move to different locations and leave the women behind. 

"Some are sold for weapons, or for just $10, or 10 cigarettes," Domle said.

For how determined they are, consult their latest video taunting and threatening the West.