Facebook's detailed metrics for advertisers helps the government campaign reach its targets - people who might be groomed online by militants."Using Facebook ads, I can go within Facebook, I can grab an audience. I can pick country X, I need age group 13 to 34, I need people who liked Abu Bakr al-Baghdadi or any other set, and I can shoot and hit them directly with messages," he said."In some places in the world, it's literally pennies a click to do it," he said.