The Daily Beast reports: On Thursday, around the same time ISIS leader Abu Bakr al Baghdadi announced that he had survived a U.S. airstrike and promised in a recorded message to “erupt volcanos of jihad,” American officials were meeting to discuss just how hard it was to track the militant group.

Baghdadi and his followers have proven exceptionally difficult to track and kill because they’re encrypting their communications and taking steps to avoid being detected by U.S. surveillance, according to several current and former officials. Without American intelligence operatives on the ground in ISIS’s home base of Syria—and with only a limited number of surveillance planes in the air—those communications are one of the only surefire ways to keep tabs on ISIS.

In addition to encryption that American officials say has proven very difficult to crack, ISIS is also using a commercially available service that permanently deletes messages sent via the Internet, making them nearly impossible to intercept, according to an individual who was briefed on the issue Thursday. This person didn’t name the service, but one application widely used in Iraq is called FireChat, which allows users to send messages to each other without connecting to the Internet. [Continue reading…]