The Islamic State has visibly attracted young Muslims from all over the world to its violent movement to build a caliphate in Iraq and Syria. But here’s what’s less visible — the online backlash against the Islamic State, also known as ISIS and ISIL, by young Muslims declaring their opposition to rule by Islamic law, or Shariah, and even proudly avowing their atheism. Nadia Oweidat, a senior fellow at the New America Foundation, who tracks how Arab youths use the Internet, says the phenomenon “is mushrooming — the brutality of the Islamic State is exacerbating the issue and even pushing some young Muslims away from Islam.”