This is what people think of when they imagine the Joint Special Operations Command, or JSOC — the secretive, über-elite military unit that killed Osama bin Laden. The leader of a JSOC unit in Iraq, known as K-Bar, gets shot in the chest by insurgents. K-Bar waves away his medic until he finishes killing his assailants. His reward? Leading JSOC’s operations in Afghanistan.

Ludicrous acts of superhuman bravado are part of JSOC’s myth and mystique. That mystique is hard to penetrate: JSOC is so secretive that it instructs its members not to write down important information, lest it be vulnerable to disclosure under the Freedom of Information Act. But a new book reveals that killing might not even be the most important thing JSOC does.

Marc Ambinder, a former reporter for The Atlantic and National Journal, goes deep inside JSOC to reveal that it has become perhaps the government’s most effective intelligence agency. Unassuming office buildings around the Washington area and beyond have become unlabeled spy centers that process untold volumes of information extracted from JSOC’s hunting missions, with such a rapid analytic turnaround time that the “shooters” of the unit can quickly begin planning their next kills. In fact, Ambinder reports in The Command, his just-published eBook, the integration of tactical spying within JSOC is so thorough that it’s hard to distinguish “shooters” from analysts.