The United States has long sought to keep secret details of intelligence gathering but over years, or decades, details emerge that confirm suspicions of who was doing what, with what to accomplish specific tasks. In early 2017 it was confirmed (perhaps by accident) that much of the effort to take down ISIL (Islamic State in Iraq and the Levant) since it appeared in 2014 has been the work of U.S. Joint Special Operations Command (JSOC). The 2017 revelations confirmed that JSOC had been responsible for most of the casualties ISIL had suffered so far. JSOC, using a combination of SOCOM (Special Operations Command) operators, similar forces from allies (both NATO and Arab as well as, unofficially, Israel) and a growing number of contractors (usually for SOCOM and other military personnel) were responsible for locating most of the 70,000 ISIL personnel killed so far. JSOC did a lot of the intel work using special equipment and techniques developed and used heavily in Iraq and Afghanistan after 2005.
Do read it all.
Or you can believe we rely on an agent who was slipped into ISIL who is radioing back vital information.
One or the other.