After an end-of-the-year video showing pre-teens hunt down and kill bound prisoners in an abandoned building, the Islamic State today released an even more gory follow-up with children as young as preschool age murdering prisoners tied to broken carnival rides. The 18-minute highly produced video out of ISIS' Khayr province in Syria was distributed through publicly accessible Islamic State media channels, social media and file-sharing sites. It begins by showing adults training in a bombed-out building, but transitions into adults leading small children in exercises. A boy about 9 or 10 years old is shown gleefully participating in a...