On twitter, facebook, messaging apps etc.? Seems like a totally unhot thing to do. Easily preventable.
I don't recall them being stopped by the FBI. All they were doing was reporting them to Twitter; nothing illegal. Speaking of which, they have declared Dec 11th to be a "Day of Rage" against ISIS http://heavy.com/news/2015/12/new-i...2015-twitter-tweets-goats-memes-announcement/
Probably because a lot of them are operated by intelligence organizations in an effort to find future terrorists or those interested in terrorist propaganda. A lot of adds for hitmen are also run by government agencies. Contact them and end up in jail.
You do realize that these guys in San Bernardino weren't recruited through social media from the available evidence? The reality is that the gov't is very limited in allowing anyone to have an account with a business. It's up to the businesses to make those decisions until a law is passed in Congress that can survive judicial review ultimately. I mean, this is what republicans want - businesses to have the power, not the gov't. And so it is.
Pretty much this. OP, which "authorities" are you referring to, and what law gives them the power to "allow" or disallow ISIS propaganda accounts?
apparently the Anonymous bozos did a pretty terrible job in their "war" against ISIS. http://gizmodo.com/anonymous-is-rea...5qEjtVQ.0&utm_referrer=https://www.google.com